Copyright: Copyright Institute of Isotopes, Budapest, Hungary


Help contents

 - Welcome to Hypermet-PC!

 - User Interfaces

 - Procedures

 - Answers to frequently asked questions (FAQ)

 - References

Note:

   You can get context-sensitive on-line help in Hypermet-PC by pressing the <F1> key.

Copyright (c) 1995-97 by Institute of Isotopes


Welcome
Welcome to Hypermet-PC!

Hypermet-PC for DOS v5.0 is a comprehensive gamma-ray spectrum processing tool with the following main modules and features:

- Unique, automatic nonlinear peak fitting algorithm for evaluating complicated gamma-ray spectra (including automatic fitting of various background shapes and multiplets).

- Quality assurance package for gamma-ray spectrometers including:

  - unique algorithms for  system nonlinearity nonlinearity, absolute and relative full-energy peak detector efficiency and FWHM (detector resolution) vs. energy curve fitting a unique curve creating algorithm

  - ADC test module

- A simple qualitative nuclide identification module for NAA and PGAA (instrumental and prompt gamma neutron activation analysis).

Hypermet-PC provides convenient solutions along with high-precision results.

Program provides:

  - carefully tested top-level algorithms;

  - easy-to-use, efficient, mouse oriented graphic user interface;

  - easy connection with other spectrum-processing tools through CSV and PTF output file formats (result files can be imported (e.g. to a spreadsheet application).

See also

   Historical background of Hypermet-PC

   Structure of Hypermet-PC program

   Spectrum evaluation with Hypermet-PC

   Typical steps of peak fitting process

   Peak fitting algorithm


Historical background of Hypermet-PC

   The original  HYPERMET code was developed in FORTRAN by Phillips and Marlow [PHILMARL] in the early seventies at the Naval Research  Laboratory, Washington D. C. for automatic and efficient analysis of multichannel pulse-height spectra using high-speed mainframe computers.

   The authors' governing principle has been to require minimal input from the user in order to save manpower and to minimise human errors. To achieve reliable results by automatic fitting, a carefully chosen semi-empirical parametrized function was adopted to represent the detector response, including all physical and statistical effects which contribute to a real spectrum.

   Hypermet-PC development started at 1991 at the Institute of Isotopes (Budapest, Hungary). Retaining most of the original fitting concepts,  the original code  was rewritten in C++ to port it to IBM compatible PCs. Advanced graphic user interface and other outstanding quality assurance modules was built in to the program which was finally brought to the market in 1995. After several internal versions, Hypermet-PC version 5.0 for DOS was released in April 1997. DOS platform was chosen following the recommendation of IAEA (International Atomic Energy Agency) to ensure the ability of evaluating complex spectra with modest hardware requirements along with a sophisticated and fully automatic peak fitting algorithm. However, development has been started to port Hypermet-PC under Windows95 operating system.

See also

   Spectrum evaluation with Hypermet-PC


Structure of Hypermet-PC program

In Hypermet-PC, specialised program modules perform different tasks.

  When you start Hypermet-PC, the Main module appears. This is a frame to load and view measured spectra stored in various input formats. For additional details, see Main module pull-down menu.

  Eval module performs automatic spectrum fitting. To start Eval module, select Eval from Main module pull-down menu. See also: Eval module pull-down menu, spectrum evaluation, fitting steps, fitting algorithm.

  Quality Assurance modules helps collecting and evaluating information about the quality of your spectrometer:

  - ADC test module for ADC linearity measurements taken with a sliding pulser train.

  - Relative and absolute full-energy peak detector efficiency calibration module

  - System nonlinearity calibration module

  - FWHM (detector resolution) calibration module

   Nuclide ID module performs a simple qualitative analysis for NAA and PGAA spectra.

  To start a Quality Assurance or the Nuclide ID module, select Options from Main module pull-down menu and then click on the appropriate menu.


User interfaces

  Hypermet-PC has an easy-to-use, efficient, mouse oriented graphic user interface. Select element of user interface to get help on:

- General layout of Hypermet-PC screen

  - Main module user screen

  - Eval module user screen

  - Nonlin module user screen

  - Efficiency module user screen

  - NuclideID module user screen

- Menus

- Pop-up windows

- Keyboard

- Mouse


Pop-up windows

   Hypermet-PC provides moveable, 3D look-and-feel pop-up windows and input controls which mimic their MS-Windows counterparts for the efficient work.

Pop-up windows (or, in Windows terminology, dialog boxes) contain different types of common control elements, such as

- press button, (rectangular captioned buttons rising from the surface of a pop-up window) which serves to abandon or confirm a group of user interactions,

- check box, (small square area which is lowered into the surface of a pop-up window, with or without a small cross in it) which request yes/no type answers from the user for a specific question,

- radiobutton, (groups of circular buttons lowered into the surface of a pop-up window, with or without a black filled circle in them) which let the user to choose from several possibilities,

- data input box, (rectangular area which is lowered into the surface of a pop-up window, with text and blinking text cursor) which offer a convenient way to edit numeric or textual data,

- scrollable list, (a list of text lines with a scroll bar on the right side) for selecting one or more element from them,

- roll-down list, (a scrollable list which can be open down or close back by pressing a button) from which rarely used elements can be chosen.

   You can select control elements by clicking with the mouse or by pressing the <Tab> or <Shift-Tab> keys. Selected status is generally indicated with blue colour, while elements in not selected status uses black colour to display their content.

   It is possible to acknowledge all the elements placed in a pop-up window by pressing the <Enter> or clicking on the OK press button.

   To abandon all changes made in the dialog box, press <Esc> or click on the small window closing press button with caption X in the upper right corner of the dialog box.

See also

   Using the mouse with pop-up windows


Using the mouse with pop-up windows

   Mouse has an exceptional role in pop-up window operations, such as selecting input control elements, pressing push buttons, opening drop-down lists and so on. In general, control elements can be either in enabled or in disabled status. Hypermet-PC uses dimmed (greyed) colours for disabled elements, whose status cannot be changed. We provide a list below to help using specific control elements:

Press button: press them with left mouse button, then release the mouse button. If you changed your mind before you released the mouse button, move away the mouse pointer and then release the button. Changes will not take effect.

Check box: to change the status of a check box to its opposite, simply click on it with the left mouse button.

Radiobutton: to choose one from several possibilities, simply click on the desired item with the left mouse button.

Data input box: when you select an input box with clicking on it, all the text contained will be selected (displayed with green background). If you start typing, all the selection will be deleted and replaced with the newly typed text. If you dont want to delete the content of the input box, simply click in the box. Then the selection disappears and blinking text cursor will be placed to the clicked letter.

Scroll bar: To scroll text to a specific direction, click on arrow points to the opposite direction (e.g. for scrolling down, press up arrow). To turn a page into appropriate direction, click on the scrollbar area between the arrows and the square dragging box. You can hold down mouse button after you pressed the arrow or the paging area: scrolling or paging will be automatically repeated.

Scrollable list: to search one item from the list, use the attached scroll bar. When you found the element to be selected, click on it with the left mouse button. If the type of the item to be selected makes it possible, multiple elements may be chosen at a time by holding down the <Ctrl> key on the keyboard, while clicking on a specific item.

Roll-down list: these lists can be open by clicking on the opener button on the right side of a static (non-editable) data input box. After pressing this button captioned with an arrow points up and down, a normal scrollable list window appears. Clicking on an item in the list, selected value appears in the static input box and the list will be closed. If you do not want to change the selection after opening the roll-down list, press the opener button and list will disappear. A good example of this control is the file type selection box placed on the Load File pop-up windows.

To abandon all changes made in the dialog box, click on the small window closing button with caption X in the upper right corner of the dialog box.

See also

   Using mouse in Hypermet-PC

   Installing mouse on your computer


Using the keyboard with pop-up windows

   Keyboard has a limited role in pop-up windows operations, because the bulk of the work is done using a mouse. However, if one prefers the keyboard, pop-up windows can be operated without almost any restriction.

   In general, control elements can be either in enabled or in disabled status. Enabled items may be selected with mouse or with the keyboard. In general, the colour of a selected control element changes emphasising the place where keyboard action takes place.

   Hypermet-PC uses dimmed (greyed) colours for the disabled elements, whose status can neither be changed nor selected by any method.

   Please note that keyboard operations effect a control element only if that element is selected with <Tab> or <Shift+Tab> keys or by clicking on it with the mouse. Selected status is generally indicated with blue colour, while elements in not selected status uses black colour to display their content.

Some of keys serve for general purposes while others function with specific control elements only, such as roll-down lists or input boxes.

 General purpose keys:

Tab: jumps to next control element.

Shift+Tab: jumps to previous control element.

Enter: confirm changes made in the pop-up window and immediately close the window.

Esc: abandon changes made using control elements and immediately close the window.

Control element specific keys:

Press button: pressing <Space> will operate a press button.

Check box and Radiobutton: to change the status of these elements to its opposite, press <Space> key.

Data input box: when you select an input box with clicking on it or with <Tab> or <Shift+Tab>, all the text contained will be selected (displayed with green background). If you start typing, all the selection will be deleted and replaced with the newly typed text. If you dont want to delete the content of the input box, simply press the <RightArrow> or <LeftArrow> keys on the keyboard.  Then the selection disappears and blinking text cursor will be moved according to the pressed key.

Scrollable list: to search one item from the list, use the <UpArrow> and <DownArrow> keys. To select an element, press <Space>. It is not possible to select multiple list elements at a time without applying mouse.

Roll-down list: these lists can be open by selecting the static (non-editable) data input box with <Tab> or <Shift+Tab> and then open the list by pressing the <DownArrow> key. Then a normal scrollable list window appears, where elements can be selected using <Space>. After selecting an element, list will be closed and selected item will be written into the static input box. A good example of this control is the file type selection box placed on the Load File pop-up windows.

See also

   Using mouse in Hypermet-PC

   Installing mouse on your computer


Using mouse in Hypermet-PC

   In Hypermet-PC, mouse is generally used for completing most tasks. In fact, we tried to design the program in a way, the user can accomplish complicated tasks without even pressing a button. The program requires a two-button standard mouse.

Mouse usage:

Main, Eval, ADC test, Nuclide ID module, left button

 - lower expanded window:  dragging and resizing the rubber band

 - upper expanded window: moving the channel cursor

Main module, right button

 - lower expanded window: dragging and resizing the rubber band

 - upper expanded window: setting or clearing ROIs

Quality Assurance modules, left and right buttons

 - in both expanded windows move the channel cursor.

Eval module, right button

 - lower expanded window: dragging and resizing the rubber band

 - upper expanded window: selecting continuous or discontinuous groups of channels: ROIs (marked with red points) or Fixed Regions (marked with blue points).

Notes:

 - in Main module user must select Display/Expand Off/On menu to switch display into expanded mode

 - in Eval module sweeping over a region while holding down the right button will result in different action dependent on whether user is looking in the Logbook or not. In the former case, blue-coloured Fixed Regions (to prepare a fit with fixed region boundaries), otherwise a simple red-coloured ROI will be selected.

See also

   Using mouse with pop-up windows

   Installing a mouse on your computer


Hypermet-PC Menus
Menus

   User can select the menus by mouse or by typing the highlighted characters while holding down the <Alt> key. For example, to select the File menu, press <Alt-F>. By using the arrows and the Enter key one can also select any menus easily using the keyboard.

In Hypermet-PC every program module has its own pull-down menu.

To get help navigate in a pull-down menu specific to a module, click on one of the followings:

  - Main module

  - Eval module

  - ADC test module

  - Nonlin module

  - Efficiency module

  - FWHM module

  - Nuclide ID module


Eval module

   Eval is the kernel module in Hypermet-PC: it performs the sophisticated evaluation of gamma spectra.

  To start Eval module, first load a spectrum in Main module using File/Open menu, then click on Eval or press <Alt-E>. A new pull-down menu appears.

   To evaluate your spectrum, you should first provide a rough peak energy and peak width calibration for two peaks in the spectrum. This is the only input needed by Eval module.

   After automatic fitting the whole spectrum, Logbook can assist the user in revising fitting results, correcting badly fitted regions and refining calibrations. Thereafter, report files can be generated and sent to a disk file or to the printer.

   If you want to know more about the steps of fitting process, fitting concepts or about the algorithm involved, choose the appropriate link below.

See also

   Eval module pull-down menu

   Typical steps of a spectrum fitting process

   Spectrum evaluation with Hypermet-PC

   Hypermet-PC fitting algorithm

   Logbook concept of Hypermet-PC


Eval module user screen

   In the Eval module the middle of the screen is always in expanded mode, when the screen is divided into two parts: lower and upper expanded window. The lower window shows the spectrum while the upper expanded window contains a magnified part of the spectrum selected by the rubber band. Rubber band is a rectangular area shown with a broken line in the lower window and can be manipulated by the mouse or by the keyboard.

   To move the rubber band, click inside the band with the left mouse button and move the mouse cursor while holding down the left button. Movement can be achieved by pressing arrow keys while holding down <Alt> key.

   To resize the rubber band, click outside the band with the left mouse button and move the mouse cursor while holding down the left button. While you move the mouse cursor, the lower left corner of the rubber band will remain in original position but the upper right corner of the rectangular rubber band will move according to the movement of the mouse. Note that a maximum size is defined for the rubber band. To resize the rubber band with keyboard, use arrow keys while holding down <Ctrl> key.

   It is possible to switch between linear and logarithmic display mode by selecting Display / Lin/Log menu or by clicking on the green LIN or LOG button at the bottom of the screen. A step-by-step transition between the two modes can also be attained by pressing the <UpArrow> or <DownArrow> keys. This way the user can scrutinise any part of a specific spectrum region.

   At the right of the screen the info page is displayed. Eval module stores here multiple pages of detailed information about the spectrum, and the result of fits. To display an info page, use <PageUp> and <PageDown> keys.

   The spectrum info page contains the spectrum header, date of measurement, elapsed and live time of the measurement, energy and FWHM calibration data, channel number of the spectrum, maximum and minimum channel counts  and sum of all counts.

   The fit info page in the upper expanded window contains detailed information about the fit. Note that fitting results are stored in an internal database, called Logbook and can be displayed by selecting Logbook / Regions or Logbook / Peaks menus. If you fit a region repeatedly, then you will have refits of the same region. To switch between refits, click on the small arrows appearing at the bottom of the fit info page.

   In the spectrum display windows a channel cursor (a small blue vertical bar) is displayed. Actual position of the channel cursor is displayed in the cursor info bar, which is a rectangular area at the bottom of the screen. The channel cursor can be moved by mouse or by pressing <LeftArrow> or <RightArrow> keys.

   If you loaded a Dual LFC spectrum, display must be switched to LFC mode using Options / Dual LFC / Uncorrected (or Corrected) menu in the Main module before you start Eval module. To switch between corrected and uncorrected spectrum parts, use the toggle CORRECTED / UNCORRECTED button at the bottom of the display.

See also

   Eval module pull-down menu

   Logbook concept of Hypermet-PC


Eval module pull-down menu

   Eval module performs the evaluation of a spectrum. Create first a rough two-point peak width and energy calibration. Perform a fit by selecting Fit menu. To fit the next region, simply select Advance menu. To review fitting results, use LogBook menu. Select Report menu to save results.

Please select a menu to get help on it:

  Return menu

  Setting menu

      Load *.set

      Save *.set

      Calibration

      Fine tune

          Sigma

          Peak

          Background

      Experts

      Nonlin opt.

      Eff opt.

      Dual opt.

  Fit menu

  Advance menu

  Report menu

      Peaklist

          File

          Screen

          Printer

      Short

          File

          Screen

          Printer

      Sampo PTF&SPE

      CSV

  Logbook menu

      Region

      Peak

  Help menu


Screen menu

(Eval module, under Report / Peaklist or Report / Short)

   Users can review the results of a spectrum evaluation on the text-mode result browser window by selecting the Screen menu under Peaklist or Short menus. The format of report depends on the menu from which the user opened the actual Screen menu.

Note

   If you are running Hypermet-PC under Windows, by selecting the Screen menu, Hypermet-PC may be switched back to the windowed environment of MS-Windows. That is, result browser window may be reduced in size. If you notice this, simply press <Alt+Enter> (hold down Alt while pressing Enter), and Hypermet-PC will be restored to full-screen.

See also

    Result Browser window

    Short Report format

    Peaklist Report format

    Eval module pull-down menu


File menu

(Eval module, under Report / Peaklist or Report / Short)

   Users can save the results of a spectrum evaluation to a disk file by selecting the File menu under Peaklist or Short menus. By clicking on the File menu a file saving pop-up window appears. Here you can specify the name and the path of the output file to be created. Pressing OK press button will save the report file. File format depends on the menu from which the user opened the actual File menu.

See also

    File Saving pop-up window

    Short Report format

    Peaklist Report format

    Eval module pull-down menu


Printer menu

(Eval module, under Report / Peaklist or Report / Short)

Users can directly print the results of a spectrum evaluation by selecting the Print menu under Peaklist or Short menus. If you attached your printer to the appropriate parallel port, simply click on the Printer menu and printing starts.

For details of printing, see Printing from Hypermet-PC.

See also

   Printing section in the FAQ


Result Browser window (text-mode browser)
Result Browser window

   Result Browser window serves for browsing of large amount of textual data. It is used, for example, to review fitting results after a spectrum evaluation or to browse the nuclide library of Nuclide ID module.

   The window is implemented by using of text mode screen, that is, before Hypermet-PC shows the browser window, switches to text display mode and after the user has finished browsing, switches back to graphical screen. This switching allows fast text display (Note: it is much faster to display large amount of data in text mode than in graphical mode).

   Result Browser window occupies almost the whole text screen. To ease the scrolling of text, mouse-sensitive scrollbars are placed near the browser window. It is possible to scroll by clicking on the arrows pointing up and down or the scroll bar itself, which will initiate paging up or down. When clicking on the Return menu, the window will be closed and the graphical screen is restored.

Keyboard may also be used to scroll the text: use arrow keys to scroll into all directions, as well as <Ctrl+Home> to jump to the beginning and <Ctrl+End> to jump to the end of the text. Pressing the <Esc> key will close the browser window and restore the graphical interface of Hypermet-PC.

Note

   If you are running Hypermet-PC under Windows and using the Result Browser window, Hypermet-PC may be switched back to the MS-Windows environment. Consequently, result browser window may be reduced in size. If you notice this, simply press <Alt+Enter> (hold down Alt while pressing Enter), and the browser window will be restored to full-screen.


Printing from Hypermet-PC

   When user select a Printer menu anywhere in Hypermet-PC pull-down menu tree, Hypermet-PC immediately prints the results directly to that parallel port, which is specified in the Printerport value under [PRINTING] section of your HYPC.INI file. Hypermet-PC simply sends ASCII text lines with maximum 80 characters per line to the printer port,  terminating every line with a CR/LF (carriage return: ASCII code 13 and line feed: ASCII code 10) character pair. This is acceptable for most printers (including laser printers).

   The parallel port which Hypermet-PC prints to depends on the value of Printerport variable in HYPC.INI file. For printing to LPT1 port, set Printerport to 1, and so on (maximum port which Hypermet-PC can use is LPT4).

Printing is performed in a completely different way under MS-DOS and MS Windows.

Under DOS:

- If you are not running any Windows version, while Hypermet-PC is running, then due to the nature of DOS programs, Hypermet-PC can not operate on other task until printing has finished.

- If the connection is lost between printer and your computer, or your printer stops accepting characters, Hypermet-PC waits for a pre-set time-out value (typically for about half a minute) to restore the connection.

- If pre-set time-out value passed and the connection have not been restored, Hypermet-PC aborts the printing process and an error message is displayed.

- Please note that the time-out value mentioned above is set by your system BIOS and not by Hypermet-PC.

Under Windows:

- If you are running Hypermet-PC under Windows, then Windows will perform the real printing operation and Hypermet-PC will be almost immediately freed from the task of printing.

- Moreover, Windows handles the printing problems consistently thus the user can expect  meaningful error messages.

See also

   Printing section in the FAQ


ADC test module (Options/Qual.Assurance menu)
ADC test module

   The ADC test utility is aimed for scanning ADC channels one by one to determine integral and the differential nonlinearity and to detect possibly defective channels.

   First read in the spectrum (which is recorded with a sliding pulse train). Next, select Options/ Qual. Assurance /ADC test.

   The program automatically determines lower and upper limits of the investigated channel range and then calculate the average count for all selected channels as well as the differential nonlinearity parameter. The whole range is displayed in the lower half, while a 20-30 channel range in the vicinity of a defective or worst channel is displayed in the upper expanded window. All calculated parameters are listed in the info page.

   A unique feature of this module is the integral linearity curve constructed from the measured spectrum. To activate this menu, select Linearity/Integral from the menu bar appearing when the spectrum and results are displayed. This way you can simply obtain the required quality parameters of your ADC.

See also

   What is differential nonlinearity?

   What is integral nonlinearity?

   ADC Test module algorithm

   ADC test module pull-down menu

   ADC Test module user screen


Algorithms involved in ADC Test module

Automatic determination of boundaries in the differential nonlinearity screen:

Starting from the first or last channel, the program finds the channel, where

1.    the count is greater then the half of the average and

2.    the slope and curvature values in 20 consecutive channels are less then the half of their statistical

       uncertainty.

Calculation of integral nonlinearity curve:

The program simply sums, integrates up the relative differences of the counts to the average.

Searching the optimal baseline for integral nonlinearity:

The nonlinearity, that is the difference of the response function from a linear function, the baseline, is depending on the choice of a linear function. The program attempts to find that linear function, where the largest difference in the investigated region is the least of all other choice of baselines.

See also

   ADC Test module  algorithm


What is differential nonlinearity of an ADC?
What is ADC differential nonlinearity?

   The linearity of a Ge spectrometers response to radiation is an important quality parameter which depends on the linearity of its components such as the amplifier, ADC, etc. Two different linearity specifications are required: the integral nonlinearity, and the differential nonlinearity.

   The differential nonlinearity specifies the non-uniformity of the ADCs channel widths. For the measurement, a sliding pulser signal (e.g. BNC PB-4 Pulser with LG-1 Ramp Generator) should be connected to the ADC input. In order to reduce the statistical error, the measurement typically takes 10-24 hours to collect sufficient data (usually 100,000 counts in each channel).

   The differential nonlinearity - expressed in percentage - is the maximum deviation of count in any channel compared to the average number of counts in all channels.

After loading a test spectrum differential nonlinearity can be determined using ADC Test module, accessible by selecting Main / Options / Qual. Assurance / ADC Test menu.

See also

   Integral nonlinearity

   ADC Test module algorithm

   ADC test module

   ADC Test module user screen


Integral nonlinearity of an ADC
What is integral nonlinearity of an ADC?

   The linearity of a Ge spectrometers response to radiation is an important quality parameter which depends on the linearity of its components such the amplifier, ADCs etc. Two different linearity specifications are required: the integral nonlinearity, and the differential nonlinearity.

   The integral nonlinearity is a measure of the deviation from an ideal, straight line energy calibration curve (which converts channel numbers to energy values). For a spectrometer this parameter can be determined by measuring a number of gamma-ray standards with well-known energies.

   This approach eliminates the need of a very stable and linear pulse generator but has disadvantage of being time consuming. The other advantage is that the whole system is tested in the same circumstances   as it is normally operated. However, this procedure is not appropriate to test  the ADC channels one by one. Consequently, in case of possible ADC malfunction the use of ADC test is recommended.

   The integral nonlinearity tester built into the ADC Test module help present the result of such a measurement for an ADC with up to 16K channel conversion gain.

   ADC integral nonlinearity can be determined using ADC Test module, which can be accessed from the Main module after loading a test spectrum by selecting Options / Qual. Assurance / ADC Test menu. After ADC Test module started, it computes the differential nonlinearity. To change the display to integral nonlinearity, select Linearity / Integral menu. Hypermet-PC automatically determines integral nonlinearity of your system and shows the results on the screen.

See also

   Differential nonlinearity

   ADC Test module algorithm

   ADC test module

   ADC Test module user screen


ADC test module pull-down menu

  ADC test module helps determine the two most characteristic parameters of your ADC: differential and integral nonlinearity. To complete this task, load a test spectrum in Main module taken with a sliding pulse train and start ADC test module. To display Integral nonlinearity, select Linearity/Integral menu. Modify boundaries of the investigated region under Setting/Region menu.

Return menu

Setting menu

    Region

    Baseline

Linearity menu

    Differential

    Integral

Help menu

See also

   What is differential nonlinearity?

   What is integral nonlinearity?

   ADC Test module user screen

   ADC test module

   Algorithm of ADC Test module


User screen in ADC Test module

   In ADC Test module it is possible to choose two totally different operation modes: differential and integral nonlinearity parameter determination. To switch from one mode to another, use Linearity menu.

   In general, the result of last performed differential or integral nonlinearity fit is shown in the middle of the screen, while info pages display additional information.

Differential nonlinearity screen

   In differential nonlinearity determination mode, the middle of the screen is divided into two parts: lower and upper expanded window. In the lower expanded window Hypermet-PC shows the spectrum part involved in the nonlinearity determination. In the upper window, the vicinity of the most defective channel is shown and the channel cursor is placed on the worst channel. In both windows, red straight lines indicate the average count, white broken lines show 1.0 sigma, while magenta broken lines show 3.0 sigma limits around the average with the computed deviation of the input data.

   Channel cursor can be moved by mouse or by pressing <LeftArrow> or <RightArrow> keys. By dragging the rubber band in the lower expanded window, magnified part can be modified (moved away or can be stretched) in the upper window.

   Detailed results of differential nonlinearity determination are displayed on the info page including: starting and ending channel of the determination, average count, deviation of counts, as well as position and deviation of the worst "defective" channel.

   Left and right boundaries of the region to be evaluated can be set by Setting / Region menu.

Integral nonlinearity screen

   In differential nonlinearity determination mode, the screen is undivided. It contains the integral nonlinearity curve, which is transformed by a linear transformation if baseline is set to optimum mode. The average is shown by a straight red line, while a 0.025% limit (typical in most high quality ADCs) is indicated using two magenta dashed lines.  The channel cursor can be moved by mouse or by pressing <LeftArrow> or <RightArrow> keys.

   Detailed results of integral nonlinearity determination are displayed on the info page such as starting and ending channel of the determination, deviation of counts in both positive and negative direction from the average and integral nonlinearity in percentage.

   Left and right boundaries of the region to be evaluated can be set by using Setting / Region menu, while Setting / Baseline menu can be used to choose from the three possible baseline determination modes.

See also

   What is differential nonlinearity?

   What is integral nonlinearity?

   ADC test module

   ADC test module pull-down menu


Return menu

(ADC test module)

   By selecting this menu, ADC Test module closes and Main module becomes active again. Because it is not possible to save the results of ADC Test module evaluation in a file, no further actions are taken as common in other Quality Assurance modules.

   To save the results of differential and integral nonlinearity fitting for a specific ADC, you can only use Print Screen function of MS-Windows to capture the content of the graphical screen or the screen dump function provided by Hypermet-PC, which will save the content of the screen into a BMP (Windows bitmap) file for further processing.

See also

  Graphic screen dump to a bitmap file

  ADC test module

   ADC test module pull-down menu


Setting menu

(ADC test module)

   The Setting menu in ADC Test module, helps fine-tune the differential or integral nonlinearity algorithm.

Available menus:

   Region:    boundaries of the analysed region can be set.

   Baseline:  the applied method can be set which is used to determine the integral nonlinearity curve for the ADC.

See also

   ADC test module

   ADC test module pull-down menu


Linearity menu (ADC test module)
Linearity menu

By selecting this menu, user can specify the type of the nonlinearity determination method used for ADCs.

Available menus:

   Differential: set applied nonlinearity determination method to differential.

   Integral:      set applied nonlinearity determination method to integral.

See also

   What is differential nonlinearity?

   What is integral nonlinearity?

   ADC test module

   ADC test module pull-down menu


Help menu

(ADC test module)

This menu serves as fast link to the on-line help available for ADC Test module.

See also

   ADC test module

   ADC test module pull-down menu


Setting / Baseline menu

(ADC test module)

   This menu can be reached only when Hypermet-PC uses integral nonlinearity method to determine quality parameters of your ADC.

Available menus:

   Optimum: program automatically fits the optimal integral nonlinearity curve so that it fits parameters for a linear transformation (shifting and stretching) which rotates the curve created from measured data points on a way where the difference will be minimal between the most defective channel and the mean line.

   Linear fit: program does not apply any transformation on input data, simply determine the mean line from input data.

   User defined: user can determine two points (channels), where mean line must intersects the curve created from the input data.

See also

   Algorithm of integral nonlinearity fitting

   What is integral nonlinearity?

   ADC test module

   ADC test module pull-down menu


Setting / Region menu

(ADC test module)

   Defines the boundaries of the input data (in channels), on which ADC Test module performs the determination of differential or integral nonlinearity curve. It may be necessary to modify these values if user wants to determine the parameters of the ADC on a specific (most often on a narrower) range.

   ADC Test module does not set these boundaries to first channel (starting point) and last channel (ending point), because in most cases an empty region (channels without counts) can be found in a normal spectrum around the first channels. If ADC Test algorithm would involve these channels in the determination of most defective channel, user would get incorrect results. Therefore when user starts ADC Test module, boundaries are set to 1% and 99% of the whole spectrum.

See also

   What is differential nonlinearity?

   What is integral nonlinearity?

   ADC test module

   ADC test module pull-down menu


What is nonlinearity?

 The linearity of a Ge spectrometers response to radiation is an important quality parameter which depends on the linearity of its components such as the amplifier, ADC, etc.

   Take a look at the gamma-ray detection process!

   When a gamma photon hits the detector , a number of charge carriers are produced being proportional of the gamma-ray energy deposited in the crystal. When the charge collection is completed and the resulting signal amplitude is converted to channel number by the ADC, one count is added to a specific channel of the collected spectrum. In ideal case, the relevant channel number of the detector signal is depending only the amount of the collected charges. In this case, for the spectrum the user should apply a linear function to convert channel numbers to energy values.

   In the real world, response of spectrometer components such as amplifiers, ADCs will influence the resulting system linearity Consequently, system nonlinearity functions should always be determined and considered in high quality gamma-ray spectrometry.

   Nonlinearity module provides a polynomial to describe the deviation of measured peak energies from the literature values, thereby improving the accuracy  of the two-point energy calibration.

See also

   Nonlinearity module

   Algorithm for computing nonlinearity curve


Algorithm for computing nonlinearity curve

   Ortho-normalised polynomials are fitted to the measured nonlinearity values, based on the Least Squares Method. Data from more different measurements can be used to determine the nonlinearity curve. These data may differ by an additive linear curve from each other. The difference is eliminated during the process by fitting the parameters of the linear curve.

See also

   What is nonlinearity?

   Nonlinearity module


Nonlinearity calibration module

   With the Nonlinearity utility you can easily determine the nonlinearity of your entire measurement system. The aim of this procedure is to improve the accuracy of the energy calibration.

 For accurate results, user should

- determine the nonlinearity of the system and check it on a regular basis for each measuring set-up using the Nonlinearity module, and

- apply the saved nonlinearity calibration file (the .LIN file) every time before creating a peaklist report in the Eval module.

   The chance is small to determine high-precision peak positions in energy units without nonlinearity calibration. This is especially important using Efficiency and Nuclide Identification modules because the applied algorithms try to locate peaks in the vicinity of their literature energy values with certain energy window (typically ± 0.5 keV) In practice, by neglecting nonlinearity calibration beside the two-point energy calibration, a rather large deviation in peak positions can be expected (1-3 channels), and incorrect uncertainty data will appear in the peaklist report files (in general, uncertainties will be smaller than the real values if user do not apply nonlinearity correction). This will prevent accurate peak identification using Efficiency or Nuclide Identification modules.

Conclusion: Nonlinearity correction results in significant improvement in accuracy on peak centroid determination and takes only a few minutes to create. Thus it is advisable to use nonlinearity correction whenever the user generates a peaklist file in Eval module.

See also:

  What is nonlinearity?

  Typical steps of the nonlinearity calibration

  Nonlinearity module pull-down menu

  Nonlinearity module user screen

  Nonlinearity module algorithm

  Details of energy calibration


User screen of Nonlinearity module

   In the Nonlinearity module the main output screen is divided into two parts: lower and upper expanded window.

   In the upper window Hypermet-PC displays the peak energy versus the deviation from the ideal straight line with the fitted nonlinearity curve. The fitted curve is drawn by a solid white line, while the standard deviation of the curve is indicated by a filled area with dark grey colour. The data points loaded by Dataset / Load menu get individual colours, and shown with a cross, where the vertical line shows the standard deviation of the measured point (uncertainty in peak position).

   In the lower window the Nonlinearity module shows the residuals (i.e. the difference between measured data and fitted curve) for individual data points in chi or keV scale. One standard deviation of data points around the fitted curve is indicated with a dark grey horizontal stripe in the middle of the residual window. Three times the standard deviation limit is also indicated with two thin grey lines.

   Channel cursor can be moved by mouse or by pressing <LeftArrow> or <RightArrow> keys in both windows.

   Info pages contain detailed information about previously loaded and fitted datasets and associated isotopes. To display the data belonging to a specific dataset, press <PageUp> or <PageDown> keys a few times.

   System specific data are displayed on the first info page, as well as left and right boundaries of the interpolated region in channels, largest deviation of the data points measured from the fitted baseline in channels, system nonlinearity in percentage, overall chi-square and coefficients of the fitted polynomial (from second order parameter) with uncertainties in the polynomial parameters.

   Dataset specific data displayed on the following info pages are: peaklist file name, number of identified gamma lines, parameters and parameter uncertainties of the linear transformation carried out on the original data points and chi-square values for isotopes contained in the dataset.

   Left and right boundaries of the region to be evaluated can be set by using Setting / Region menu, while Setting / Baseline menu can be used to choose from the three possible baseline determination modes.

See also:

   What is nonlinearity?

   Nonlinearity module

   Typical steps of the nonlinearity calibration

   Nonlinearity module pull-down menu

   Nonlinearity module algorithm

   Details of energy calibration


Typical steps of nonlinearity calibration

To create a nonlinearity calibration:

1)  Measure some multi-gamma sources (calibrated or home-made 182-Ta, 152-Eu, 56-Co, etc.)  at the same  spectrometer setting (0  2 MeV/8K, etc.).

2)  Load all spectra one by one and evaluate them in Eval module with two-point energy calibration. Then save fitting results in Hypermet-PC Short, Peaklist or Sampo-90 PTF Report format.

3)  Start nonlinearity module by selecting Options / Qual. Assurance / Nonlin menu.

4)  Load a previously saved peaklist file into Nonlin module with Dataset / Load menu.

5)  Select one or more nuclides from the pop-up window (you can specify several nuclides at a time holding down <Shift> key while selecting nuclides with the left mouse button) and initiate a nonlinearity curve fitting.

6) Repeat steps 4-5 for the other spectra.. Subsequent curves will be normalised to the first dataset thus resulting a final nonlinearity calibration function.

7) If other spectrometry calibration settings are also required (e.g. 0 - 3.2 MeV / 8K for short lived NAA, etc.) repeat steps 1-6 to obtain an other nonlinearity curve.

Notes:

  -  Nonlinearity module uses Nuclid.std file to offer a list of nuclides at Step 5. If you can not find your preferred nuclide, quit Hypermet-PC and insert the data of isotopes into this file with a text editor (Notepad, etc.). Next time you start Hypermet-PC, changes take effect.

  -  If Nonlinearity module could not identify enough gamma lines, try to increase the identification threshold value under Setting / Polynomial. First drop the loaded dataset by pressing <PageUp> a few times and selecting Dataset / Remove. After you dropped the dataset, load it in again by selecting Dataset / Load. Identification of gamma lines will be made using new threshold values.

See also

    What is nonlinearity?

    Nonlinearity calibration module

    Algorithm for computing nonlinearity curve

    Nonlinearity module user screen


Nonlin module pull-down menu
Nonlinearity module pull-down menu

   With the Nonlinearity utility you can easily determine nonlinearity of your entire measurement system. First load evaluated data by using Dataset / Load. Then select isotopes involved in the actual measurement by the left mouse button while holding down <Shift>. If results are not acceptable, remove dataset (press <PageDown> key to select and Dataset / Remove to drop it away). Increase identification threshold under Setting / Polynomial and load back the dataset again.

File menu

   New

   Open

   Save

   Save as

   Return

Setting menu

    Polynomial

    Baseline

    Residual

    Grid

Dataset menu

    Load

    Remove

Calculate  menu

Report menu

    Short

    CSV

Help menu

See also

   What is nonlinearity?

   Nonlinearity calibration module

   Typical steps of the nonlinearity calibration

   Nonlinearity module user screen


File menu (Nonlin module)
File menu

(Nonlinearity module)

   File menu helps manage nonlinearity log files (which will contain all data necessary to reproduce the whole nonlinearity curve, including data points, literary data of nuclides and fitting parameters) and quit from Nonlinearity module.

   Sub-menus in File menu make it possible to load a previously created nonlinearity log file, to save a newly created one or save it using another file name. Using Return menu, user can leave Nonlinearity module and return to Main module.

Available menus:

   New

   Open

   Save

   Save as

   Return

See also

   What is nonlinearity?

   Nonlin module pull-down menu


File / New menu (Nonlin module)
File / New menu

(Nonlinearity module)

   Selecting this menu, Nonlin module creates a new nonlinearity log file, which will contain all data necessary to reproduce the whole nonlinearity curve, including data points, literary data of nuclides and fitting parameters.

   Using this menu the previous nonlinearity log file will be closed and screen and info page will be cleared. User can load new datasets (measured data points) to determinate the nonlinearity of the system on which the measurement were taken by selecting Dataset / Load menu.

   User can save the newly created nonlinearity log file by selecting the File / Save menu.

See also

   What is nonlinearity?

   Nonlin module pull-down menu


File / Open menu (Nonlin module)
File / Open menu

(Nonlinearity module)

  Selecting this menu, Nonlin module opens a previously saved nonlinearity log file which contains all data necessary to reproduce the whole nonlinearity curve, including data points, literary data of nuclides and fitting parameters.

   After opening the selected file, a previous nonlinearity fit will appear on the screen and detailed information will be shown on the info pages. User can then load new datasets, delete whole datasets or individual measurement points, change parameters of fit and can save the modified nonlinearity fit using File / Save or Save as menus. To abandon changes, simply quit from the Nonlinearity module.

Note:

   Default file extension for nonlinearity log files is LIN.

See also

   What is nonlinearity?

   Nonlin module pull-down menu


File / Save menu (Nonlin module)
File / Save menu

(Nonlinearity module)

   Selecting this menu, Nonlin module saves the nonlinearity log file, which contains all data necessary to reproduce the whole nonlinearity curve, including data points, literary data of nuclides and fitting parameters.

   If you make some modifications on a previously saved nonlinearity file (e.g. adding new datasets, deleting data points or modifying the parameters of the polynomial), changes will be saved in the log file.

   If you newly created a fit, save it for a directory which serves as a common folder for a specific measurement system to store the quality assurance log files together.

   If you want to abandon changes, simply quit from the Nonlinearity module and thus e the new fit will not be saved to a disk file.

Note:

   Default file extension for nonlinearity log files is LIN.

See also

   What is nonlinearity?

   Nonlin module pull-down menu


File / Save as menu (Nonlin module)
File / Save as menu

(Nonlinearity module)

   Selecting this menu, Nonlin module saves the nonlinearity log file, which contains all data necessary to reproduce the whole nonlinearity curve, including data points, literary data of nuclides and fitting parameters.

   If you make modifications on a previously saved nonlinearity file (e.g. adding new datasets, deleting data points or modifying the parameters of the polynomial), changes will be saved in another log file. This way user can make nonlinearity curves  for different settings.

   If you newly created a fit, this menu identical with the Save menu to save nonlinearity log files.

See also

   What is nonlinearity?

   Nonlin module pull-down menu


File / Return menu (Nonlin module)
File / Return menu

(Nonlinearity module)

   Selecting this menu Nonlinearity calibration module ends and control returns to the Main module.

   If you did not save the modified or newly created nonlinearity log file, then Hypermet-PC remind you of saving the log file.

See also

   Nonlin module pull-down menu


Setting menu (Nonlin module)
Setting menu

(Nonlinearity module)

  By selecting Setting menu in Nonlinearity module, user can customise both the fitting algorithm and the display properties of the fitted results.

Available menus:

    Polynomial: for setting the order of the polynomial used in the fit and threshold values used during gamma line identification

    Baseline: for setting the method used during fitting of the nonlinearity curve

    Residual: for setting the type of residual data displayed in the lower quarter of the screen

    Grid: enables or disables the grid in the upper window.

See also

   Nonlin module pull-down menu


Polynomial menu
Setting / Polynomial menu

(Nonlinearity module)

   When user select this menu, a pop-up window appears with three data input boxes. Changing the data may affect the result of the nonlinearity curve fitting process.

   Degree: gives the order of polynomial applied to fit the input data points. Typically, a second to seventh order polynomial ensures suitable approximation for a Ge detector nonlinearity curve.

   Thresholds for

  - identification: Nonlinearity module attempts matching of measured and literary peaks in the loaded datasets and in the Nuclid.std file. Peaks will be selected for the fit if a measured peak energy is within the given uncertainty of the  literature peak energy value plus and minus  the above threshold value.

  - acceptance of CHSQ: On the info page chi-square values belonging to isotopes will be indicated with green or red colour. The colour depends on a pre-set value : if chi-square for an isotope is less than this threshold value, then it will turn into green , otherwise into red.

Notes:

  - If the program could find only a few gamma lines for a multi-line gamma source, try to increase slightly the identification threshold. After you changed the threshold value, changes take effect only if you remove the whole dataset by using of Dataset / Remove menu and by loading it back by Dataset / Load.

See also

   Nonlin module pull-down menu


Setting / Baseline menu

(Nonlinearity module)

   Nonlinearity module in Hypermet-PC uses a unique and sophisticated method to determine system nonlinearity Among others it is possible to determine the optimal baseline, i.e. when the nonlinearity of the system is the least possible value. Moreover, it is also possible to determine the system nonlinearity automatically with the commonly defined baseline or with manual setting of the baseline intersections.

   By selecting Setting / Baseline menu, user can set the method for baseline determination.. Three options are available:

   Optimum: In this baseline determination mode, Nonlin determines the optimum baseline, where the nonlinearity is the smallest possible. This is performed by a linear transformation of input data. In general, when an Optimum baseline is determined, deviation of the data points from the baseline is identical in positive and  negative direction. Largest deviations (in channel) are displayed on the info pages and indicated with MIN and MAX.

   Linear fit: This is the most commonly used baseline determination method fitting a straight line to the input data points, and minimising chi-square during the fit. The resulting line will be used as baseline for determining the deviation of data points from the ideal linear energy calibration. As usual, the determined system nonlinearity is significantly higher here than at the optimum nonlinearity determination mode. This proves that the optimum method is independent from the actual numerical values of data points when determining the baseline, while the Linear fit method is not. Therefore, results obtained with the latter method  can not be used as a figure-of merit  when comparing different measuring set-ups.

   User defined: In this baseline determination mode user can set manually the baseline position, by giving two intersection points (in channel). Initial values are those obtained by either Optimal or  Linear fit mode. With this method the user can estimate the errors introduced when neglecting nonlinearity corrections or by using not appropriate calibration energies (A typical case is the use of 60-Co and 241-Am sources for calibrating a spectrometer with 0 - 3.2 MeV energy range. Large deviations can be expected around 3 MeV!)

See also

   Nonlin module pull-down menu


Setting / Residual menu

(Nonlinearity module)

   By selecting this menu, user can specify the type of the residual data displayed in the lower quarter of the screen. User can choose one from the three options below:

   None: switches off the residual window.

   Chi: switches residual window to display the differences between data points and the fitted curve in chi-square units. Scale is indicated with a dark grey stripe (fitted curve plus/minus one standard deviation) and with two dark grey lines (three standard deviation limit).

   Difference: switches residual window to display the differences between data points and the fitted curve in energy units (in keV). Scale is automatically normalised to the maximum deviation value and the zero difference from the fitted line is indicated with a horizontal dark grey line in the middle of the residual window.

See also

   Nonlin module pull-down menu


Setting / Grid menu

(Nonlinearity module)

   By selecting this menu, a grid can be switched on or off for the upper nonlinearity curve displaying window.

   For horizontal gridlines, the strong line indicates the baseline, while the others are drawn at every 1 keV distance from the baseline.

   For vertical gridlines, the strong line indicates the 0 keV point of the energy scale, while the thin ones are at every 1000 keV.

See also

   Nonlin module pull-down menu


Dataset menu

(Nonlinearity module)

   In Nonlinearity module, Dataset serves to load measurement data from a saved peaklist file or to drop an entire dataset which is previously loaded.

Load: Loads a peaklist for the actual nonlinearity fit.

Remove: Drops a peaklist data and remove it from the actual nonlinearity fit. This menu is available only if user pressed the <PageUp> or <PageDown> keys to display the relevant dataset data on the info page.

See also

   Nonlin module pull-down menu


Calculate menu

(Nonlinearity module)

   By selecting this menu, Nonlinearity module automatically calculates the baseline and the nonlinearity curve for the input data. In general, an automatic fit is performed after loading a new data set or dropping one or more peaks or after modifying fitting parameters. Thus, this menu is required only if user deletes the fitted curve (and therefore de-normalises the input data sets). To delete the fitted curve, click on the green button DATA in the cursor info bar to switch to CURVE mode and press <Del> key.

See also

   Nonlin module pull-down menu


Report menu

(Nonlinearity module)

   By selecting this menu, user can generate either a short or an extensive report of the actual nonlinearity fit.

Available menus:

Short: generates a short report from the current fit in text format. Short report contains deviation and chi-square data for all data points, basic parameters of the fit, boundaries of the interpolated region, the parameters of the fitted polynomial and the nonlinearity of the whole system in percentage. This report can be directly printed out.

CSV: generates an extensive report from the current fit in CSV format. The report file contains the same data as stored in the short format, plus detailed numerical results of the fit, as well as parameters of the ortho-normalised polynomials, parameters of the X-axis transformation and the base line, finally the variance-covariance matrix of the fit. It is not advisable to directly print out this report, but this format ideal for further processing in popular spreadsheets programs (EXCEL, etc.).

See also

   Nonlin module pull-down menu


Help menu

(Nonlinearity module)

This menu serves as fast link to the on-line help available for Nonlinearity module.

See also

   Nonlinearity calibration module

   Nonlin module pull-down menu


Efficiency calibration module

   With the Efficiency utility you can easily determine the full-energy  peak efficiency versus gamma-ray energy function of your detector. The aim of this module is to provide an easy-to use and fully automated method for determining the relative or absolute detector efficiency curves with the least possible user interaction. The provided polynomial efficiency curve can be used for comparing different detectors, as well as for analytical computations. Moreover, users can generate an efficiency corrected peak list report in the Eval module using a previously created detector efficiency curve.

   For efficiency-corrected peaklist generation, user should

  - determine the efficiency curve of the system with the Efficiency module, and

  - apply the saved efficiency calibration file (the .EFF file) before creating a peaklist report in the Eval module.

   There are two types of the efficiency curves produced by Efficiency module: relative and absolute efficiency curves.

   For relative efficiency curves, user should measure some spectra with different gamma-ray sources. It is important that they have several gamma-lines (182-Ta, 110m-Ag, etc.) but their source activities  should not necessarily be absolutely calibrated.. After evaluating all the measured spectra, user should load them into Efficiency module by using Dataset / Load menu and selecting one or more isotopes present in the source. Efficiency module will automatically normalise all the datasets to that loaded first and places each data point to a common efficiency curve.

   For absolute efficiency curves, the process is identical with that  listed above with a minor difference: you should make measurements with one or more absolutely calibrated sources as well and load them into Efficiency module by using Dataset / Load Abs menu. By selecting this menu, a pop-up window appears with the list of source certificates already entered into Nuclid.std file. User should select the source, then the calculation of an absolute efficiency curve is made automatically.

Notes:

  -  Data sets of absolutely calibrated sources are not normalised together, so if large deviation exists between absolute efficiency data points, user should check weather: the calibration data is properly set in Nuclid.std file; the radiation source is leakproof; the spectra are taken under the same circumstances.

  -  User can select gamma line and radiation source data from Nuclid.std. If user could not find a specific isotope in the isotope selection window, then quit Hypermet-PC and edit Nuclid.std (insert the isotope data).

See also

   What is detector efficiency?

   Typical steps of the efficiency calibration

   Efficiency module user screen

   Efficiency module algorithm

   Efficiency module pull-down menu

   Nuclid.std file


Typical steps of the efficiency calibration

To create an efficiency curve:

1)  Measure some spectra (e.g. 5 spectra) with different radioactive sources (absolutely calibrated or not calibrated home-made) and with the same source-detector geometry.

2)  Load all spectra one by one and evaluate them in Eval module applying a two-point energy calibration and nonlinearity correction. Then save fitting results in Hypermet-PC Short, Peaklist or Sampo-90 PTF Report format.

3)  Start Efficiency module with selecting Options / Qual. Assurance / Efficiency menu.

4)  Load a previously saved peaklist into Efficiency module with Dataset / Load menu. If you have taken a measurement with an absolutely calibrated source, then use Dataset / Load Abs menu.

5)  Select nuclide(s) according to current peaklist in the pop-up window  (you can specify several nuclides at a time with the left mouse button  while holding down <Shift> key. )Or, if you have taken the measurement with an absolutely i calibrated source, then select the relevant source from the source list.

6)  Load all peaklists into Efficiency module (repeat steps 4-5). Peaklists will be normalised to the first dataset and the Efficiency calibration will be automatically adjusted after loading each dataset. If an absolutely  calibrated source is also involved in the efficiency curve determination, then all  datasets will be normalised to the absolute calibrated one.

7)  If results are not meaningful (missing lines, etc.), change settings by using Setting menu.

Notes:

  -  Efficiency module uses Nuclid.std file to offer a list of nuclides or sources in Step 5. If you could not find your preferred nuclide or source, quit Hypermet-PC and edit this file: insert the data of missing isotopes or sources. Next time you start Hypermet-PC , these changes will take effect.

  -  If Efficiency module can not identify all  gamma lines associated with a selected nuclide, try to increase the identification threshold value under Setting / Polynomial. Then drop the loaded dataset by pressing <PageUp> a few times and selecting Dataset / Remove. After you dropped the dataset, load it in again by selecting Dataset / Load. Identification of gamma lines will be made using new threshold values.

See also

    What is detector efficiency?

    Efficiency module user screen

    Efficiency module algorithm

    Efficiency module pull-down menu

    Nuclid.std file


User screen of Efficiency module

   In the Efficiency module the middle of the screen is divided into two parts: lower and upper expanded window.

   In the upper window Hypermet-PC displays detector efficiency versus peak energy. The fitted curve is drawn by a solid white line, while the standard deviation of the curve is indicated by a filled area with dark gray colour. The data points loaded by Dataset / Load (or Load Abs) menu get individual colours, and shown with a cross, where the vertical line shows the standard deviation of the measured point (uncertainty of the detector efficiency is computed from the uncertainty of the peak intensity and from the uncertainty of the peak area).

   In the lower window the Efficiency module shows the residuals (i.e. the difference between measured data and fitted curve) for individual data points in chi-square or percentage scale. One standard deviation of data points around the fitted curve is indicated with a dark grey horizontal stripe in the middle of the residual window. Three times the standard deviation limit is indicated with two thin grey line. Lower expanded window can be switched off by selecting Setting / Grid / None menu.

   Channel cursor can be moved by mouse or by pressing <LeftArrow> or <RightArrow> keys in both windows.

   Info pages contain detailed information about previously loaded and fitted datasets and about isotopes associated with  the given dataset. To display the data belonging to a specific dataset, press <PageUp> or <PageDown> keys a few times.

   System specific data displayed on the first info page together with as left and right boundaries of the interpolated region in keV, overall chi-square and coefficients of the fitted polynomial with uncertainties in the polynomial parameters.

   Dataset-specific data displayed on the following info pages: peaklist file name, isotope name, number of identified gamma lines, parameters and parameter uncertainties of the linear transformation which is carried out on the original data points and chi-square values for the dataset. If the dataset is loaded as absolute calibrated gamma-ray source, then additional information indicated on the info page: name of the source, certified activity, date of certification, date of spectrum measurement, elapsed time during the measurement and half-life of the selected nuclide.

See also

   What is detector efficiency?

   Typical steps of the efficiency calibration

   Efficiency module user screen

   Efficiency module algorithm

   Efficiency module pull-down menu


Algorithm involved in Efficiency module

   Ortho-normalised polynomials are fitted to the measured efficiency points, based on the Least Squares Method. The energy and the efficiency scales are both logarithmic. Absolute and relative efficiency data can also be fitted together. The normalisation factors between the efficiency curves are fitted during the process until the differences are eliminated.

   Individual absolute efficiency points, derived from the same gamma-source, are correlated to each other, because they were calculated with common parameters as half-life and activity of the gamma-source. The correlation is also taken into account in the calculation to avoid unrealistic uncertainty estimation for the fitted curve.

See also

   What is detector efficiency?

   Efficiency module pull-down menu


What is detector efficiency?

   Detector efficiency is the ratio of the number of gamma photons hitting the detector and the number of signals the detector produces as output. Detector efficiency has a well-defined dependency on the energy of gamma photons.

   The function which describes the efficiency versus gamma photon energy is the detector efficiency curve.

   In Hypermet-PC, a maximum of  8-th order polynomial constitutes the detector efficiency curve. The curve can be constructed with some measurements  on gamma-ray sources utilising Efficiency calibration module.

See also

   Efficiency calibration module

   Efficiency module pull-down menu


Efficiency module pull-down menu

   With the Efficiency utility you can easily determine the efficiency curve of your detector: load peaklist by using Dataset / Load or by Load Abs if the measurement was taken by absolute  calibrated gamma-ray source. Select isotopes or sources involved in the actual measurement with the left mouse button while holding down <Shift. If results are not acceptable, remove dataset (press <PageDown> key to select and Dataset / Remove to drop it away). Increase identification threshold under Setting / Polynomial and load the dataset again.

File menu

   New

   Open

   Save

   Save as

   Return

Setting menu

    Polynomial

    Residual

    Grid

Dataset menu

    Load

    Load Abs.

    Remove

Calculate  menu

Report menu

    Short

    CSV

Help menu

See also

   Typical steps of the efficiency calibration

   Efficiency module user screen

   Efficiency module

   What is detector efficiency?


File menu

(Efficiency module)

   File menu helps manage efficiency log files (which will contain all data necessary to reproduce the whole efficiency curve, including data points, literary data of nuclides and fitting parameters) and quit from Efficiency module.

   Sub-menus in File menu make it possible to load a previously created efficiency log file, to save a newly created one or save it using another file name. Using Return menu, you can leave Efficiency module and return to Main module.

Available menus:

   New

   Open

   Save

   Save as

   Return

See also

   What is detector efficiency?

   Efficiency module pull-down menu


File / New menu

(Efficiency module)

   Selecting this menu, Efficiency module creates a new efficiency log file (*.EFF), which will contain all data necessary to reproduce the whole efficiency curve including data points, literary data of nuclides and fitting parameters.

   Using this menu the previous efficiency log file will be closed and screen and info page will be set to blank. User can load new datasets (measured data points) to determinate the efficiency of the detector on which the measurement were taken by selecting Dataset / Load menu. If user has a measurement with an absolute intensity calibrated gamma-ray source,  then Dataset /Load Abs. must be used instead.

   After efficiency curve determination has successfully ended, user can save the newly created efficiency log file by selecting the File / Save menu.

See also

   What is detector efficiency?

   Efficiency module pull-down menu


File / Open menu

(Efficiency module)

  Selecting this menu, Efficiency module opens a previously saved efficiency log file, which contains all data necessary to reproduce the whole efficiency curve including data points, literary data of nuclides and fitting parameters.

   After the user selected the file to open, previous efficiency fit will appear on the screen and detailed information will be shown on the info pages. User can then load new datasets, delete whole datasets or individual measurement points, change parameters of fit and can save the modified fit using File / Save or Save as menus. If user want to abandon changes, simply quit from the Efficiency module without saving the new fit.

Note:

   Default file extension for efficiency log files is EFF.

See also

   What is detector efficiency?

   Efficiency module pull-down menu


File / Save menu

(Efficiency module)

   Selecting this menu, Efficiency module saves the efficiency log file, which contains all data necessary to reproduce the whole efficiency curve including data points, literary data of nuclides and fitting parameters.

   If you loaded a previously saved efficiency file and made some modifications in the fit (e.g. added new datasets, delete data points or modified the parameters of the polynomial), changes will be saved in the log file.

   If you newly created a fit, save it for a directory which serves as a common folder for a specific measuring system to store the quality assurance log files together.

   If you want to abandon changes, simply quit from the Efficiency module and do not save the new fit to a disk file.

Note:

   Default file extension for efficiency log files is EFF.

See also

   What is detector efficiency?

   Efficiency module pull-down menu


File / Save as menu

(Efficiency module)

   Selecting this menu, Efficiency module saves the efficiency log file, which contains all data necessary to reproduce the whole efficiency curve including data points, literary data of nuclides and fitting parameters.

   If you loaded a previously saved efficiency file and made some modifications in the fit (e.g. adding new datasets, deleting data points or modifying the parameters of the polynomial), changes will be saved in another log file. This way user can make experiments with different settings.

   If you newly created a fit, this menu identical with the Save menu, that is it serves to save efficiency log files.

See also

   What is detector efficiency?

   Efficiency module pull-down menu


File / Return menu

(Efficiency module)

   Selecting this menu Efficiency calibration module ends and control returns to the Main module.

   If you did not save the modified or newly created efficiency log file, then Hypermet-PC remind you of saving the log file.

See also

   Efficiency module pull-down menu


Setting menu

(Efficiency module)

  By selecting Setting menu in Efficiency module, user can customise both the fitting algorithm and the display properties of the fitted results.

Available menus:

    Polynomial: for setting the order of the polynomial used in the fit and threshold values used for gamma line identification

    Residual: for setting the type of residual data displayed in the lower quarter of the screen

    Grid: enables or disables the grid in the upper efficiency curve displaying window.

See also

   Efficiency module pull-down menu


Polynomial menu (Efficiency module)
Setting / Polynomial menu

(Efficiency module)

   A pop-up window appears with a data input box.

   Degree: gives the order of polynomial applied to fit the input data points. Typically, a 2nd to 8th order polynomial ensures suitable approximation for a Ge detector efficiency curve.

See also

   Efficiency module pull-down menu


Setting / Residual menu

(Efficiency module)

   By selecting this menu, user can specify the type of the residual data displayed in the lower quarter of the screen. User can choose one from the three options below:

   None: switches off the residual window.

   Chi: switch residual window to display the differences between data points and the fitted curve in chi-square units. Scale is indicated with a dark grey stripe (fitted curve plus/minus one standard deviation) and with two dark grey lines (three standard deviation limit).

   Difference: switch residual window to display the differences between data points and the fitted curve in percentage. Scale is automatically normalised to the maximum deviation value and the zero difference from the fitted line is indicated with a horizontal dark grey line in the middle of the residual window.

See also

   Efficiency module pull-down menu


Setting / Grid menu

(Efficiency module)

   By selecting this menu, grid can be switched on or off for the upper efficiency curve displaying window. In Efficiency module the display is always set to log-log display mode (both energy and efficiency axes are displayed in  logarithmic scale).

   Horizontal gridlines are drawn at every efficiency value where the mantissa of the efficiency value is an integer.

   Vertical gridlines are drawn at every 100 keV on a logarithmic scale.

See also

   Efficiency module pull-down menu


Dataset menu

(Efficiency module)

   In Efficiency module, Dataset helps load measurement data from a saved peaklist file or drop an entire dataset which is previously loaded. Datasets may be obtained from measurements taken by absolutely calibrated gamma-ray sources or by not calibrated ones.

Available menus:

Load: Loads a peaklist which is taken by a measurement from a non-calibrated source and include it to the actual efficiency fit.

Load Abs: Loads a peaklist which is taken by a measurement from an absolutely  calibrated gamma-ray source and include it to the actual efficiency fit.

Remove: Drops a peaklist data and remove it from the actual efficiency fit. This menu is available only if user pressed the <PageUp> or <PageDown> keys to display the dataset data on the info page.

See also

   Efficiency module pull-down menu


Calculate menu

(Efficiency module)

   By selecting this menu, Efficiency module automatically calculates the efficiency curve for the input data. In general, an automatic fit is performed after loading a new data set or dropping one or more peaks or after modifying fitting parameters. Thus, this menu is necessary only if user deletes the fitted curve (and therefore de-normalises the input data sets). To delete the fitted curve, click on the green button DATA in the cursor info bar to switch to CURVE mode and press <Del> key.

See also

   Efficiency module pull-down menu


Report menu

(Efficiency module)

   By selecting this menu, user can generate either a short or an extensive report of the actual Efficiency fit.

Available menus:

Short: generates a short report from the current fit in simple text format. Short report contains efficiency, deviation and chi-square data for all data points, basic parameters of the fit, boundaries of the interpolated region, the parameters of the fitted polynomial and the overall normalised chi-square. This report can be directly printed out.

CSV: generates an extensive report from the current fit in CSV format. The report file contains the same data as stored in the short format, plus detailed numerical results of the fit, as well as parameters of the ortho-normalised polynomials, parameters of the X-axis transformation, the variance-covariance matrix of the fit, finally calculated values of the efficiency curve for a wide energy range. It is not advisable to directly print out this report, but this format is ideal for processing it in spreadsheets programs.

See also

   Efficiency module pull-down menu


Help menu

(Efficiency module)

This menu serves as fast link to the on-line help available for Efficiency module.

See also

   Efficiency module

   Efficiency module pull-down menu


Return menu

(Eval module)

By selecting this menu, Eval module ends and Main module becomes active. Before leaving Eval module, user can decide to keep or abandon fitting results by saving or deleting the evaluation log file (*.LOG).

Note:

   Please remember that Hypermet-PC does not store the applied two-point energy and peak width calibration in the log file. To retain the calibration data, user should select Setting / Save *.set menu and specify a setting file name to store these data.

See also

    Eval module pull-down menu


Setting menu

(Eval module)

   By selecting Setting menu, user can set proper energy and peak width calibration and configure peak fitting algorithm.

Available menus:

Load *.set: loads a previously saved setting file to apply two-point energy and peak width calibration

Save *.set: saves a setting file

Calibration: creates two-point energy and peak width calibration

Fine tune: changes parameters which are related to the peak fitting algorithm

Experts: changes all pre-set values for the peak fitting algorithm

Nonlin opt.: loads a nonlinearity log file (*.LIN) for nonlinearity correction

Eff. Opt.: loads an efficiency log file (*.EFF) for efficiency correction

Dual opt.: Switches to corrected or uncorrected part of the Dual LFC spectrum

See also

    Eval module pull-down menu


Load *.set menu (Eval module)
Setting / Load *.set menu

(Eval module)

   By selecting of this menu, a setting file loading window appears. The user should specify the name of a *.SET file to load. The setting data which the SET file contains overwrites the actual settings, therefore user can set back a previously saved two-point energy and peak width calibration as well as parameters for the fitting algorithm.

See also

   Setting files (*.SET)

   Eval module pull-down menu

   Setting menu


Save *.set menu (Eval module)
Setting / Save *.set menu

(Eval module)

   By selecting of this menu, a setting file saving window appears. The user should specify the name of a *.SET file to save actual parameters necessary to restore the status of Eval module to perform the evaluation of the actually loaded spectrum.

Saved parameters:

  - two point energy calibration data

  - two point peak width (FWHM) calibration data

  - fine tuning parameters for the peak fitting algorithm

Notes:

  -  For a detailed description of the saved parameters, see description about SETTING CALIBRATION and SETTING EXPERTS sections of HYPC.INI file.

  -  See also details of automatic overwriting of the calibration data

See also

   [SETTING CALIBRATION] section

   [SETTING EXPERTS] section

   Setting files (*.SET)

   Setting menu

   Eval module pull-down menu

   Fine tune menu


Calibration menu (Eval module)
Setting / Calibration menu

(Eval module)

  By selecting this menu, a calibration window appears, where user can set the method of energy calibration and define the two-point energy and FWHM calibration data points.

See also

   Usage of Calibration pop-up window

   Setting menu

   Eval module pull-down menu


Fine tune menu (Eval module)
Setting / Fine tune menu

(Eval module)

   By selecting this menu, user can modify most important parameters for peak fitting algorithm through a user-friendly interface.

Available menus:

Sigma: changes thresholds for various criteria

Peak: sets options which directly affect the fitting of peaks in the actual region

Background: enables or disables different types of background shapes

Note:

   All of the initial variables can be modified by selecting Setting / Experts menu. However, this may be a more complicated task than using Fine Tune menu, because in the former case all the parameters must be set according to the expectations of the original HYPERMET program.

See also

   Peak fitting algorithm

   Eval module pull-down menu

   Setting menu


Fine tune/Sigma menu (Eval module)
Fine tune / Sigma menu

(Eval module, Setting menu)

   By selecting this menu, a pop-up window appears with three data input boxes where user can modify thresholds for various criteria applied in the Eval module peak fitting algorithm.

Sigma limits to change:

Convergence: when the normalised chi-square of the fit is less than one plus this number multiplied by the estimated standard deviation of the chi-square distribution, the program considers the fit successful. Otherwise, if it is enabled, attempts to find a new peak in the residual. Decrease that value if you want the program to look for further peaks in the residual.

Peak search: threshold value used during the peak searching sub-algorithm (achieved by applying the negative smoothed second difference as filter function). The higher this value, peaks with less area will be found by peak searching algorithm, but the probability of determining statistical noise as peak will be also higher.

Residual search: the threshold value applied when the algorithm searches new peaks in the residual after a fit is performed.

See also

   Peak fitting algorithm

   Eval module pull-down menu

   Setting menu


Fine tune / Peak menu (Eval module)
Fine tune / Peak menu

(Eval module, Setting menu)

   By selecting this menu, a pop-up window appears with data input boxes placed in two sections where user can specify peak width properties and define limits used during fitting of skew parameters.

Gaussian width section

  - User can define the applied method for fitting of peak width (may switch off or on the Variable Peak Width Option):

    Common: Common peak width value is fitted for all peaks in the selected region. This is the default setting.

    Variable: Hypermet-PC fits individual peak width for all peaks in the actual region. Cautions: See notes

  - Minimum and maximum: The fitting algorithm enables to vary the peak width within these boundaries around the initial estimation. These values are applied as multipliers for the estimated value to compute the lower and upper limits for the FWHM. For example, if the limits are 0.70 and 1.30, then the algorithm permits the peak width to vary  30 % in both directions.

Skew section

- A max: maximum amplitude of the skew to be fitted (relative to the peak amplitude).

- B max: maximum width of the skew to be fitted (relative to the peak width).

Notes:

  - All these values should be changed with caution. User can easily produce erroneous results by  improper settings.

  - The estimated value of the peak width is computed from the two-point squared FWHM function.

See also

   Setting menu

   Peak fitting algorithm

   Eval module pull-down menu

   Variable Peak Width Option


Fine tune / Background menu (Eval module)
Fine tune / Background menu

(Eval module, Setting menu)

   User can disable or enable the components of the fitted background individually by the help of the pop-up window

Curve: controls the second-order polynomial background curve component

Tail: directs the algorithm to fit an exponential tail on the left side of the peak

Step: controls whether algorithm applies the step function or not.

   By default, all the background components are switched on. It is advisable to switch off a component only in a very rare case, when the user is absolutely sure in that the affected background component does not exist.

See also

   Peak fitting algorithm

   Eval module pull-down menu

   Setting menu


Experts menu (Eval module)
Setting / Experts menu

(Eval module)

  This menu is intended for expert HYPERMET users only, because all of the initial variables can be modified which are applied in the automatic fitting process. These parameters must be set according to the expectations of the original HYPERMET program.

   It is advisable to use the Fine Tune menu to modify fitting parameters. This is more convenient and the fitting process will not be adversely affected by improper setting of these variables.

   For details about these values see description of the SETTING EXPERTS section of HYPC.INI file.

Note:

  These values should be changed with caution. User can easily  produce erroneous results by  improper settings.

See also

   SETTING EXPERTS section

   Eval module pull-down menu

   Setting menu


Nonlin opt. menu (Eval module)
Setting / Nonlin opt. menu

(Eval module)

   You can set nonlinearity correction for your spectrum using Nonlin opt. menu. This task needs a previously created nonlinearity file.

Available menus:

Load: to load your previously created nonlinearity file. A file open window appears, which let you select your *.LIN file (saved by Nonlinearity calibration module). Hypermet-PC will then use the selected nonlinearity correction when converts channel positions to energy values. The corrected energy values appear immediately on the screen and in the report files after you have loaded your nonlinearity calibration file. Peak position uncertainties are also corrected according to error propagation rules (in general, the uncertainties of the peak positions becomes larger).

On: if you previously switched off the nonlinearity correction, you can enable it by selecting this menu.

Off: switches off nonlinearity correction of peak positions. Use this menu if you do not want to use your loaded nonlinearity calibration file. After selecting this menu, Hypermet-PC will not use nonlinearity correction and thus peak positions will appear with their uncorrected values and uncertainties.

Note:

  - This task needs a previously created nonlinearity calibration log file created by the Nonlinearity module.

  - It is possible to automatically load a specific nonlinearity calibration log file by setting NonlinFile variable under SETTING CALIBRATION section of HYPC.INI.

See also

    Setting menu

    Nonlinearity calibration module

    Typical steps of the nonlinearity calibration


Eff opt. menu (Eval module)
Setting / Eff opt. menu

(Eval module)

   You can set efficiency correction for your spectrum using Eff opt. menu. Using efficiency correction, a previously created efficiency file will be used to compute theoretical peak areas, having been measured with  an ideal detector with efficiency value 1.0 at every peak energies.

Available menus:

Load: to load your previously created efficiency file. A file open window appears, which let you select your *.eff file (saved by Efficiency calibration module). If you select a valid efficiency file, Hypermet-PC will automatically calculate efficiency-corrected peak areas. Corrected peak areas appear immediately on screen (on info pages) and in all report file generated after switching on this correction mode. Peak area uncertainties are also corrected according to error propagation rules (in most cases uncertainties will increase).

On: switches on efficiency correction of peak areas.

Off: switches off efficiency correction of peak areas. Use this menu if you do not want to use your loaded efficiency calibration file. Thereafter, Hypermet-PC wont use efficiency correction and peak areas will get back their uncorrected values and uncertainties.

Note:

  - This task needs a previously created efficiency curve. Detector efficiency curves can be simply determined by the help of the Efficiency Module.

  -  It is possible to load automatically a specific efficiency calibration log file by setting EfficiencyFile variable under SETTING CALIBRATION section of HYPC.INI.

See also

    Setting menu

    Efficiency calibration


Dual opt. menu (Eval module)
Setting / Dual opt. menu

(Eval module)

   The menus are dimmed unless you switched on the LFC option in the Main module under the Options / Dual LFC menu. If selection has been made, then user can switch between the corrected and uncorrected part of the spectrum using following menus:

Corrected: switches to corrected part of your LFC spectrum (usually the first part of the whole spectrum)

Uncorrected: switches to uncorrected part (usually the second part of the whole spectrum)

See also

    LFC (Loss Free Counting method)

    Setting menu


Fit menu

(Eval module)

   By selecting this menu, the Fitting Start Window appears with several data input boxes and check boxes. User can specify the region boundaries to fit, overwrite the estimated peak width value for the searched peaks and can specify the method of the fit.

   By pressing the OK press button, Hypermet-PC performs automatic fitting of the previously loaded spectrum.

User can perform special types of evaluation:

Only ROIs: if user have set ROIs (independently selected spectrum areas), then it is possible to evaluate only the selected ROIs from the entire spectrum.

With fixed region: User can re-define the region boundaries after a previous fit by sweeping with the right mouse button over the channels to include them in the fit (if the result of the previous fit is displayed from the Logbook). The channels selected for the following fit are signed with blue points.

Peak integration: to fit peaks with distorted shape (which can occur if the counting rate is high during spectrum accumulation or in other special cases), Hypermet-PC provides a very simple peak integration function simply to count the counts between the boundaries of the region over a linear background. To initiate a peak integration, user must select a Fixed Region.

Automatic: when a fit is performed on the actual region, program automatically defines the next region and fits it until the end of the spectrum is reached.

   The most convenient way to initiate the fit of the next region is to select the Advance menu (if user does not perform an automatic fit of the entire spectrum).

See also

   Fitting Start Window

   Setting menu


Advance menu

(Eval module)

  By selecting Advance menu, Hypermet-PC checks whether the last operation was a spectrum fit. If it was, then the peak fitting algorithm automatically selects the next region after the previous fit and initiate a peak evaluation on the newly selected spectrum part.

   During fitting of the next region, the status of the ROI checkbox and the value of the Try parameter will be retained. The Peak Integration function will not be used, even if the ast fit was performed with that option.

See also

   Fit menu

   Setting menu


Report menu

(Eval module)

   By selecting this menu, Hypermet-PC stores the fitting results in report files with appropriate peak position, peak width and uncertainty data.

   The peak positions are always stored in channels in the report files. To place energy values for the fitted peaks, user must supply proper energy calibration (for the best results, user may create a nonlinearity calibration). If the user previously created an absolute efficiency calibration for the measuring set-up , then efficiency correction may be applied to obtain absolute intensity values for the measured peaks.

The fitted results can be stored in different file types:

   Peaklist report: detailed text format report

   Short report: short text format report

   Sampo PTF&SPE report: binary report in Sampo-90 file format

See also

    Nonlinearity correction

    Efficiency correction

    Setting menu


Report / Peaklist menu

(Eval module)

   Hypermet-PC peaklists are simple text files intended to store detailed data of spectrum evaluation results (fitted peaks). These report serves as result files for end-users or for further processing in Quality Assurance and Nuclide ID modules.

Eval module stores the following parameters in peaklist report files:

  - chi-square / sigma limit

  - peak position in channel and keV

  - peak position uncertainty in keV

  - fitted peak FWHM in keV

  - fitted peak area and its error in percentage

Note:

  - The peak positions are always stored in channels in the report files. To place energy values for the fitted peaks, user must supply proper energy calibration (for the best results, user may create a nonlinearity calibration). If the user previously created an absolute efficiency calibration for the measurement system, then efficiency correction may be applied to obtain absolute intensity values for the measured peaks.

See also

    Nonlinearity correction

    Efficiency correction

    Peaklist report format

    Setting menu


Peaklist report format

   Hypermet-PC peaklists are simple text files intended to store detailed data of spectrum evaluation results. These report serves as result files for end-users or for further processing in Quality Assurance and Nuclide ID modules.

   The rows in Hypermet-PC peaklists contain no more than 80 characters. Extension of peaklist files is 'PKL'.

In the first row the date of the evaluation and the names of the binary spectrum and the evaluation log file are placed. The spectrum title obtained from the binary spectrum is placed in the second row.

From the third line to the peaklist header, variable number of lines with additional information appear::

  - Acquisition date of spectrum,

  - Nonlinearity correction file name,

  - Efficiency correction file name, etc.

The next two line is the peaklist header, then data of fitted peaks is stored in space-separated fixed width columns:

  - Peak number

  - chi-square / sigma limit

  - peak position in channel

  - peak position in keV

  - peak position uncertainty in keV

  - fitted FWHM in keV

  - peak area in counts

  - relative peak area uncertainty in percentage

Notes: If a region  has refits, only the last fit is stored for that region which one the user left on the screen.

- If there is no energy calibration during evaluation, peak energies are not stored.

- If you have chosen efficiency corrected mode, Eval module saves the intensities (counts/sec corrected with detector efficiency curve) instead of counts.

- Peak widths are the same within a region if user did not use the Variable Peak Width Option.

- The header lines of the peaklist file may change accordingly to the stored values.

See also

   Short report format


Short report format

   Hypermet-PC short reports are simple text files intended to store detailed data of spectrum evaluation results (fitted peaks). These report serves as result files for end-users or for further processing in Quality Assurance and Nuclide ID modules.

   The rows in a Hypermet-PC short file contains  maximum  80 characters. Extension of short report files is 'SHO'.

   In the first row the date of the evaluation and the names of the binary spectrum and the evaluation log file are placed. The spectrum title obtained from the binary spectrum is placed in the second row.

From the third line to the short report header, variable number of lines appear: with additional information:

  - Acquisition date of spectrum,

  - Nonlinearity correction file name,

  - Efficiency correction file name, etc.

The next two line is the short report header, then data of fitted peaks is stored in space-separated fixed width columns:

  - peak position in keV

  - peak position uncertainty in keV

  - peak position in channels

  - peak position uncertainty in channels

  - peak area in counts

  - peak area uncertainty in counts

  - fitted FWHM in keV

  - uncertainty of fitted FWHM in keV

  - chi-square / sigma limit in percentage

Notes:

- If some of the regions have refits, only the last fit is stored for a region which one the user left on the screen.

- If there is no energy calibration during evaluation, peak energies are not stored.

- If you have chosen efficiency corrected mode, Eval module saves the peak intensities (counts/sec corrected with detector efficiency curve) instead of counts.

- Peak widths are the same within a region if user did not use the Variable Peak Width Option.

- The header lines of the short report file may change accordingly to the stored values.

See also

   Peaklist report format


Report / Short menu

(Eval module)

   Hypermet-PC Short Report Files are simple text files intended to store detailed data of spectrum evaluation results. These report serves as result files for end-users or for further processing in Quality Assurance and Nuclide ID modules.

Eval module stores following parameters in the Short report files:

  - peak position and uncertainty in keV

  - peak position and uncertainty in channels

  - fitted peak area and its uncertainty in counts

  - fitted peak FWHM with uncertainty in keV

  - chi-square / sigma limit in percentage

Note:

  - The peak positions are always stored in channels in the report files. To place energy values for the fitted peaks, user must supply proper energy calibration (for the best results, user may create a nonlinearity calibration). If the user previously created an absolute efficiency calibration for the measurement system, then efficiency correction may be applied to obtain absolute intensity values for the measured peaks.

See also

    Nonlinearity correction

    Efficiency correction

    Peaklist report format

    Setting menu


Report / Sampo PTF&SPE menu

(Eval module)

   Hypermet-PC is able to store the detailed data of spectrum evaluation results in Sampo-90 file formats, therefore user may ensure the portability of the fitting results between Hypermet-PC and an application which requires fitting results and spectrum files in Sampo 90 format. Moreover, the PTF reports serves as input for Quality Assurance and Nuclide ID modules. With this option the result files are fully compatible and thus can be processed with the KAYZERO/SOLCOI NAA program package

Eval module stores following parameters in PTF report files:

  - peak position and uncertainty in channels and in keV

  - peak energy and uncertainty in keV

  - fitted peak area in counts and its relative uncertainty in percentage

  - chi-square of fitted regions

  - start of acquisition

See also

   Short report format

   PTF file format

   Peaklist report format

   Setting menu


Report / CSV menu

(Eval module)

   By selecting this menu, user can generate an extensive listing of all peak parameters  found during  evaluation. This file is stored in CSV format, which is generally used for spreadsheet applications as input.

Data fields stored in the CSV file:

(Sigma is always the standard deviation of the preceding data)

- peak position and uncertainty in keV (Energy, Sigma)

- peak position and uncertainty in channels (Position, Sigma)

- chi-square values of the fitted regions (CHSQ, Sigma)

- amplitude of the Gaussian curve (Ampl., Sigma)

- full width at half maximum of the Gaussian curve (Width, Sigma)

- full width at half maximum of the peak with skew curve (Fwidth Sigma)

- peak area and uncertainty of area (Area, Sigma)

- amplitude of the skew curve in the peak, relative to the Gaussian amplitude (A, sigma)

- width of the skew curve in the peak, relative to the Gaussian width (B, Sigma)

- coefficient of the zero order part of the background (Background, Sigma)

- coefficient of the first order part of the background (Slope, Sigma)

- coefficient of the second order part of the background (Curv, Sigma)

- amplitude of the step function in the background, relative to the Gaussian amplitude (Step, Sigma)

- amplitude of the tail function in the background, relative to the Gaussian amplitude (Tail, Sigma)

- width of the tail function in the background, relative to the Gaussian width (V, Sigma)

- left and right channels of the region (Left, Right)

- average background under the whole region (AvgBkg)

See also

   CSV report format

   Short report format

   PTF file format

   Peaklist report format

   Setting menu


Logbook menu

(Eval module)

   After an evaluation, Hypermet-PC stores all the fitting details in an internal database called logbook. User can open the logbook by selecting the Logbook / Region or Logbook / Peak menu in the Eval module, and then may select a fitted result from the logbook to review. The fitted results are displayed on the upper half of the screen and in the residual window. Residual window can be switched on by pressing the green button captioned SPECT at the bottom of the screen.

Available menus:

Region menu: lets the user to select a region to display or to delete.

Peak menu: used to display, delete or insert a peak.

  If user selects one of these menus, an appropriate pop-up window appears. User can perform operations on regions or peaks by using Region Window or Peak Window.

Note:

   Some of the operations depend on whether the logbook is opened or not. For example, when user press the right mouse button in the upper expanded window, ROIs or Fixed Regions are selected according to the status of the logbook.

See also

   Region menu

   Region Window

   Peak menu

   Peak Window

   Setting menu

   Logbook concept of Hypermet-PC


Logbook / Region menu

(Eval module)

   After an evaluation, Hypermet-PC stores all the fitting details in an internal database called logbook. User can open the logbook by selecting the Logbook / Region or Logbook / Peak menu in the Eval module, and then may select a fitted result from the logbook to review. The fitted results are displayed on the upper half of the screen and in the residual window. Residual window can be switched on by pressing the green button captioned SPECT at the bottom of the screen.

   If user selects Logbook / Region menu, a region specifying pop-up window appears. User can display or delete the region by the help of this window.

See also

   Region Window

   Peak menu

   Peak Window

   Setting menu

   Logbook concept of Hypermet-PC


Logbook / Peak menu

(Eval module)

   After an evaluation, Hypermet-PC stores all the fitting details in an internal database called logbook. User can open the logbook by selecting the Logbook / Region or Logbook / Peak menu in the Eval module, and then may select a fitted result from the logbook to review. The fitted results are displayed on the upper half of the screen and in the residual window. Residual window can be switched on by pressing the green button captioned SPECT at the bottom of the screen.

   If user selects Logbook / Peak menu, a peak specifying pop-up window appears. User can display, insert or delete peaks by the help of this window.

See also

   Peak Window

   Region menu

   Region Window

   Setting menu

   Logbook concept of Hypermet-PC


Main module

   After you start Hypermet-PC, the Main module appears. This is a frame where you can read spectra  with various file formats and can save them in ASCII or Sampo90  file formats.

   You can magnify a specific spectrum part if you switch on Expanded spectrum display mode by selecting Display / Expand Off/On menu and drag the rubber band in the lower expanded window to the desired part of the spectrum. You can set linear or logarithmic display mode using Setting / Lin/Log menu or pressing the green button captioned with LIN or LOG on the cursor info bar (at the bottom of the screen).

   If your spectrum is taken in Dual LFC (Loss Free Counting) mode, then you must switch to Dual mode by selecting Options / Dual LFC / Uncorrected menu (selecting Corrected menu will display the corrected spectrum half).

   To evaluate the spectrum, select Eval menu.

   To obtain information about the quality  of your measuring set-up, select the appropriate menu under Options / Qual. Assurance.

   To perform a simple qualitative nuclide identification, start Nuclide ID module by selecting Options / Nuclide ID.

 See also

   Main module pull-down menu

   User screen of Main module


User screen of Main module

   In the Main module the middle of the screen can be in expanded or normal mode. In expanded mode, the screen is divided into two parts: lower and upper expanded window. To switch expanded mode on or off, use Setting / Expand Off/On menu.  In normal mode, the middle of the screen is occupied by the spectrum which the user previously loaded by using  File / Open menu.

   In expanded mode, the lower window shows the spectrum while the upper expanded window contains a magnified part of the spectrum selected by the rubber band. Rubber band is a rectangular area shown with dashed line in the lower window and can be manipulated by  mouse or from the keyboard.

   To move the rubber band, click inside with the left mouse button and move the mouse cursor while holding down the left button. Movement can be achieved by pressing arrow keys while holding down <Alt> key.

   To resize the rubber band, click outside with the left mouse button and move the mouse cursor while holding down the left button. While you move the mouse cursor, the lower left corner of the rubber band will remain in original position but the upper right corner of the rectangular rubber band will move according to the movement of the mouse. Note that the maximum size is limited for the rubber band. To resize the rubber band from keyboard, use arrow keys while holding down <Ctrl> key.

   It is possible to switch between linear and logarithmic display mode by selecting Display / Lin/Log menu or by clicking on the green button captioned LIN or LOG at the bottom of the screen.

   At the right of the screen the info page is displayed. Main module shows here detailed information of the spectrum, as well as spectrum header, date of measurement, elapsed and live time of the measurement, energy and FWHM calibration data, channel number of the spectrum, maximum and minimum channel count and sum of all channel counts.

   In the spectrum displaying windows, a channel cursor (a small blue vertical bar) is displayed. Actual position of the channel cursor is displayed in the cursor info bar, which is a rectangular area at the bottom of the screen. The channel cursor can be moved by mouse or by pressing <LeftArrow> or <RightArrow> keys.

   If  a Dual LFC spectrum is loaded, display mode must be switched to LFC mode using Options / Dual LFC / Uncorrected (or Corrected) menu. You should use this setting with caution: the Dual LFC mode remains switched on even if you load a non-LFC spectrum. In this case you can get incorrect results during spectrum evaluation.

Note:

   Default settings of displaying modes can be set if user modifies the values of variables placed in HYPC.INI file under [HYPC INITIAL] section.

See also

   Main module

   Main module pull-down menu


Main module pull-down menu

   After you start program, the Main module appears first. To invoke Eval module (spectrum evaluator), select Eval. For gathering / displaying information about the quality of your detector system, select Options/Qual. Assurance and appropriate menu. If you decide to make a nuclide identification based on a previously performed evaluation, select Options / NuclideID. If you loaded an LFC spectrum, then you should switch on the LFC option using Options / Dual LFC menu.

   Please select a menu to get help on it:

File menu

Open

Write

Exit

Display menu

Line/Dots

Lin/Log

Display/Group

Expand Off/On

ROI menu

Load

Save

Clear

Eval menu

Options menu

Qual. Assurance

Nuclide ID

Dual LFC

Help menu

See also

   Main module

   User screen of Main module


File menu

(Main module)

   By selecting File menu, user can load a binary spectrum to display or to evaluate, save the previously loaded spectrum or quit Hypermet-PC.

Available menus:

   Open loads a spectrum file and displays it

   Write saves a spectrum file either in ASCII or Sampo 90 SPE format

   Exit quits Hypermet-PC

   Main module pull-down menu


File / Open menu

(Main module)

  By selecting this menu a pop-up window appears and you can load a spectrum file from a  device. Because of  several different spectrum formats, you must select the spectrum format first and then the spectrum file.

Available spectrum formats:

 S100      *.mca - CANBERRA S-100 MCA's

 AccuSpec  *.dat - AccuSpec MCA's

 ORTEC     *.chn - ORTEC MCA cards

 SAMPO-90  *.spe - created by SAMPO-90

 Genie-PC  *.cnf - created by Genie-PC

 ASCII     *.asc - ASCII spectra

 DCHYP     *.spl- compressed format

 Nucleus   *.spm - Nucleus spectrum

 Silena    *.dat - Silena spectrum

Note:

   User may re-define the default spectrum type which is offered by the file loading window if edits the content of the HYPC.INI settings file, in the [HYPC INITIAL] section. Next time when she starts Hypermet-PC, new settings will take effect.

See also

   Main module pull-down menu

   Spectrum loading window


Canberra S-100 spectrum format

   This is a binary spectrum format developed by Canberra, Inc. Energy calibration is included.


AccuSpec spectrum format

   This is a binary spectrum format. Energy calibration, and initial peak width estimation are included.


ORTEC spectrum format

   This is a binary spectrum format developed by Ortec, Inc. Energy calibration, and initial peak width estimation are included.


Sampo-90 spectrum format

   This is a binary spectrum format generated by Sampo-90 program.


Genie-PC spectrum format

   This is a binary spectrum format generated by Genie-PC program. (Genie-PC is a Canberra developed spectrum analyser software.)

WARNING:

  Genie-PC spectrum format reading is UNDER ONSTRUCTION. User should use this option with caution.


Nucleus spectrum format

   This is a binary spectrum format.


Silena spectrum format

   This is a binary spectrum format. Energy calibration is included.


ASCII spectrum format

Spectrum files in  ASCII format are simple text files making it possible to evaluate specific spectra whose formats are not supported by Hypermet-PC. Every row in text file must contain a decimal integer in ASCII format.

Content of ASCII spectrum files:

- The channel number should be placed into the first row (e.g. 8192)

- Next rows contain measured counts in appropriate channel (first channel's count is in the second text row and so on).

Sample detail of an ASCII spectrum (content of the first 8 channels from a 16K spectrum):

16384

0

0

1

8

29

131

24

11

.

.

As seen, an ASCII spectrum does not contain energy or peak width (FWHM) calibration data.


DCHYP spectrum format

   This spectrum format is developed at the Institute of Isotopes for the original HYPERMET code. It may contain more spectra in compressed form. This is a disk space saving method and makes it possible to store a series of measurements together. Typical compression ratio for spectra is 3 : 1.


File / Write menu

(Main module)

   User can save the loaded spectrum in ASCII or Sampo-90 spectrum format by selecting this menu in the Main module, This way a simple spectrum conversion may be accomplished.


File / Exit menu

(Main module)

   Selecting this menu Hypermet-PC ends.

   There is only one type of information set by the user which may lost by quitting Hypermet-PC: the actual ROI setting. If actual ROI settings should be retained, then select ROI / Save menu and specify a file name to save present settings.

See also

   Main module pull-down menu


Display menu

(Main module)

  With the sub-menus of Display menu user can customise the spectrum appearance on the display.

Available menus:

   Line/Dots

   Lin/Log

   Display Group

   Expand Off/On

Note:

   User may re-define the default display settings by editing the content of HYPC.INI settings file, in the [HYPC INITIAL] section. Next time when you start Hypermet-PC, new display settings will take effect.

See also

   Expanded mode

   Main module pull-down menu


Line/Dots menu (Display menu)
Line/Dots menu

(Main module)

   Selecting this menu, user can change the spectrum display mode on screen: toggles between line- and dot-based drawing mode. In line-based drawing mode some channel contents which have to be drawn on the same screen position, will be shown only with one line. In dot-based drawing mode these channel contents will be signed with individual dots.

   This switching of drawing modes can be seen in expanded mode only in the lower expanded window (upper half of screen is always in dotted mode).

See also

   Expanded mode

   Main module pull-down menu


Lin/Log menu (Display menu)
Lin/Log menu

(Main module)

   Selecting this menu, user can change the spectrum display mode on screen: toggles between logarithmic and linear drawing mode on the vertical axis.

   This switching works in all spectrum displaying screens, that is in upper and lower expanded window (in expanded mode) and in not expanded spectrum display mode.

See also

   Main module pull-down menu

   Expanded mode


Display Group menu

(Main module)

   By selecting this menu, user can display a specific spectrum part in the Main module spectrum displaying window.

Available sub-menus:

Full: displays the full spectrum.

First Half: displays the first half of full spectrum.

Second Half: displays the second half of full spectrum.

1st Quarter: displays the first quarter of full spectrum.

2nd Quarter: displays the second quarter of full spectrum.

3rd Quarter: displays the third quarter of full spectrum.

4th Quarter: displays the forth quarter of full spectrum.

If expanded mode is switched on (Display / Expand Off/On menu), then the selected spectrum part appears in the lower expanded window.

See also

   Main module pull-down menu


Expand Off/On menu

(Main module)

   User can switch to expanded mode display by selecting this menu.

   In the Main module the middle of the screen can be in expanded or normal mode. In normal mode, the middle of the screen is occupied by the spectrum previously loaded by using of File / Open menu.

   In expanded mode, the screen is divided into two parts: lower and upper expanded window. The lower window shows the spectrum, while the upper expanded window contains a magnified part of the spectrum selected by the rubber band.

See also

   The Hypermet-PC screen

   Main module pull-down menu


What is ROI?

ROI = Region Of Interest

   ROIs are widely used in  spectrum evaluation.. ROI means an independently selected spectrum segment, needed first when not all the peaks but only some user-selected areas are interesting for analysis..

   For example: during an analysis   not all components but only a few trace elements need to be determined in an irradiated sample characterised by  a few peaks of a specific isotope. User can define the neighbourhood of these peaks as ROIs and should perform an evaluation for these regions only, thereby reducing the time needed for the evaluating process.

    ROIs should not be confused with Fixed Regions. ROIs are shown as red points in Main or Eval module and multiple ROIs can be independently selected. Fixed Regions (showed as blue points) can be used in Eval module only and serve for fixing region boundaries within the actual region only. ROIs can be saved and reloaded , but Fixed Regions are temporarily only: and disappear after the fit is completed.

   Both ROIs and Fixed Regions can be selected using right mouse button by sweeping over a specified spectrum area. Results of selection depend on whether user is looking at the Logbook or not. If Logbook is opened for browsing, then Fixed Regions will be selected, otherwise ROIs.

See also

   ROI menu

   Main module pull-down menu

   Logbook concept in Hypermet-PC


ROI menu

(Main module)

   During routine work, sometimes there is no need to evaluate all peaks from a spectrum, but only a smaller part of it with a few peaks.

   To achieve this , use ROIs, which mean independently selected spectrum areas. After the boundaries of some regions are specified, you may start Eval module and set Fit / ROI checkbox. If ROIs are selected, then Hypermet-PC evaluates the selected ROIs only.

   Using ROIs, time consuming evaluations of problematic regions (e.g. low energy parts of spectra with convoluted X-rays and gamma-rays) may be dramatically reduced.

   To create ROIs, see ROI creating.

   You may also load or save ROI files using the ROI / Load or ROI / Save menu. You can clear all of the ROIs from the spectrum using the ROI / Clear menu.

See also

   What is ROI ?

   Main module pull-down menu


ROI creating

   User can create a ROI in the Main or in the Eval module. If Eval module is active, then you must switch off  displaying  the Logbook before creating a ROI. To switch off the Logbook click in the lower expanded window outside of the residual window (if it is open). The evaluation results displayed in the upper expanded window disappear.

   By pressing the right mouse button and dragging over a portion of the spectrum you can mark ROIs. You can also use the < and > keys for this purpose. Starting from inside of a ROI you can delete one side of the ROI, or split the ROI into two pieces. A single ROI can be deleted by moving the cursor onto the ROI and pressing the <Del> key. If you use expanded mode you can perform ROI operations only in the upper expanded window.

See also

   What is ROI ?

   Expanded mode

   Roi menu

   Main module pull-down menu


ROI / Load menu

(Main module)

   User may load previously saved ROI files by selecting ROI / Load menu. Loaded ROIs can be used the same way like those created with the mouse or from the keyboard.

See also

   What is ROI ?

   Roi menu

   Main module pull-down menu


ROI / Save menu

(Main module)

   You may save ROI files using this menu. Selecting this menu a standard file saving box appears, where the output ROI file name can be specified. Selecting New button the ROI filename get an identical name to the spectrum filename, but its extension is set to ROI. You can modify the name of the ROI file or accept it by pressing the OK button.

See also

   What is ROI ?

   Roi menu

   Main module pull-down menu


ROI / Clear menu

(Main module)

   By selecting this menu, you may delete all ROIs have been set in the spectrum. If you saved actual ROI settings with Save menu, you can restore them  using ROI / Load menu).

See also

   What is ROI ?

   Roi menu

   Main module pull-down menu


Eval menu

(Main module)

   By selecting this menu Eval module (gamma spectrum evaluator) starts. In Eval module user can automatically create peak list reports in ASCII format from the raw binary spectrum to a disk file or directly to the printer. Eval module provides a fully automatic superior peak fitting algorithm to determine peak positions, peak widths, various background shapes (linear, second order curve, step), peak tails etc.

See also

   Spectrum evaluation with Hypermet-PC

   Typical steps of spectrum fitting process

   Main module pull-down menu


Options menu

(Main module)

   By selecting Option menu, the optional program modules can be reached (i.e. which can be y purchased separately to  Hypermet-PC main program).

Available options::

   - Quality assurance modules  to characterise your spectrometer.

   - Nuclide ID for nuclide identification of INAA and PGAA spectra.

   - Dual LFC for processing spectra measured in Loss Free Counting spectrometer mode.

See also

   Main module pull-down menu


Options / Qual. Assurance menu

(Main module)

   By selecting this menu, a sub-menu offering quality assurance modules appears. These optional program modules can be applied to determine the quality  of your detector-analyser measuring set-up.

Available Quality Assurance modules:

   ADC Test: determines differential and integral nonlinearity parameters of an ADC from a spectrum recorded with a sliding scale pulser train.

   Nonlin: starts Nonlinearity module, which determines nonlinearity parameters of the entire spectrometer.

   Efficiency: determines relative or absolute full-energy peak efficiency curve for a given measuring geometry.

   FWHM: determines resolution vs. energy function .at a given spectrometer setting.

See also

   Main module pull-down menu


Nuclide ID menu
Options / Nuclide ID menu

(Main module)

   By selecting this menu, Nuclide Identification program module starts. In order to achieve nuclide identification for spectra recorded during   NAA or  PGAA (instrumental neutron or prompt gamma activation analysis) , load the spectrum in the Main module by selecting File / Open menu.

   Evaluate the spectrum with Eval module and save the  results in Short or Peaklist report format. Then quit Eval module and start Nuclide ID program module (while the spectrum file remains loaded). Load the saved peaklist file by using File / Load peaklist menu and select Analyze menu to start the analysis. If you are evaluating an NAA spectrum, set the cooling time parameter in order to apply half-life filtering of nuclides. User can review the analytical results with Report / Screen menu.

See also

   Nuclide ID module

   Nuclide ID module pull-down menu

   Main module pull-down menu


Options / Dual LFC menu

(Main module)

   With spectrometers equipped with the Dual Spectrum LFC module  you can measure simultaneously LFC (Loss Free Counting) corrected and uncorrected spectra. In this special tandem file format the first half  contains  the uncorrected while the second half the LFC-corrected measurements.. To handle Dual LFC spectra and perform correct evaluation according to the laws of statistics, you must switch to Dual LFC mode when loading  such spectra.

   By selecting Options / Dual LFC menu, a pop-up window  appears with three choices:

   Corrected: treats actually loaded spectrum as it would be measured with Dual LFC hardware.. After switching, only the corrected part is showed on the screen.

   Uncorrected: treats actually loaded spectrum as it would be collected with Dual LFC hardware.. After switching, only the uncorrected part is showed on the screen.

   Off: Switches off the Dual LFC mode.

Notes:

  -  It is possible to switch between the corrected and uncorrected part by pressing UNCORR and CORR captioned green buttons on the cursor info bar (at the bottom of the screen).

  -  If you switched on Dual LFC Mode and load a new spectrum which is not measured with Dual Spectrum LFC mode, Hypermet-PC will not automatically switch back to non-Dual LFC mode. If  then  an evaluation is initiated, you may get incorrect results.

See also

   Dual LFC (Loss Free Counting) method

   Main module pull-down menu


Help menu

(Main module)

   You can invoke on-line help from Hypermet-PC by pressing <F1> key. To ease the copying or information in Hypermet-PC help file developed for a DOS platform, we provide a Windows version of the help file with the same content. Both DOS and Windows versions of the help file (HYPDOS.HHF and HYPC.HLP) must reside in the Hypermet-PC main directory.

   If you choose Help menu in Main module, Contents and About sub-menus appear.

   With Contents menu, you can invoke on-line help. Help system is divided into several parts:

- help to succeed various tasks of Hypermet-PC

- help about Hypermet-PC menus,  keyboard and mouse usage

- answers to frequently asked questions (FAQ)

   Selecting About menu an information box appears with the recent version number of Hypermet-PC and additional information how to contact the authors.

See also

   Main module pull-down menu


Hypermet-PC Tasks

Following list provides a list of main Hypermet-PC tasks:

 Spectrum evaluation

 Energy calibration for a spectrum

 Setting ROIs

 Efficiency calibration of a detector

 FWHM calibration

 Nonlinearity calibration

 ADC test module

 Nuclide identification


Energy calibration

Hypermet-PC has a sophisticated concept for the energy calibration:

1)  Two-point energy calibration is used for a rough, approximate calibration only. This method assumes a linear function between channel number and gamma energy. Two-point energy calibration can be set in the Eval module, by selecting Setting / Calibration menu. This calibration should be set for all spectra whenever you perform a spectrum evaluation, but it is possible to save and to reload your two-point calibration using a setting file (*.SET).

2)  Along with the two-point calibration, a nonlinearity calibration curve (a second to eighth order polynomial) can compensate the nonlinearity of the components (amplifiers, ADCs etc.) of the spectrometer, therefore highly accurate energy calibration can be achieved. Determination of the nonlinearity curve should be made regularly (for example, once in a month) for every i detector-analyser system setting.(For example: 0 - 2 MeV and 0-3.2 MeV for an 8K ADC) To initiate a nonlinearity determination, start Nonlinearity module. Nonlinearity calibration can be applied by loading a previously saved .LIN file for each spectrum evaluation using Setting / Nonlin opt. / Load menu in Eval module.

User can provide energy calibration information for a spectrum

  - from the HYPC.INI file (loaded at program start)

  - from the loaded spectrum, if it contains calibration data (e.g. *.DAT files recorded by ACCUSPEC MCA cards)

  - from the default SET file which is specified in the [EVAL FIT] section of the HYPC.INI file

  - from a SET file by using Setting / Load *.set menu in Eval module

  - by creating a new calibration using Setting / Calibration menu in Eval module

Notes:

- You can disable energy calibration in the Eval module by selecting Setting /Calibration /No energy. In this state no energy values appear in screen and report files.

- Some types of binary spectra (e.g. AccuSpec) contains approximate linear energy calibration. Loading such a spectrum the pre-set values stored in the spectrum come into operation with the highest priority).

See also

   Setting files (*.SET)

   Nonlinearity calibration

   Overwriting of calibration data


FWHM calibration module

  Among other quality assurance factors, FWHM (that is the energy resolution) has a great importance in gamma-ray spectrometry. To simplify the procedure for determination   a detector resolution vs. energy curve, Hypermet-PC contains an FWHM Calibration Module.

  The concept of creating an FWHM curve is similar to other Quality Assurance modules built-in into Hypermet-PC: user should evaluate first some spectra, save peak lists and load them all into FWHM module. For every peak list, user should specify isotopes involved in the process and then the FWHM curve will be calculated automatically supposing a square root dependence between resolution and energy. However, user can change parameters involved fitting (e.g. identification properties of peaks).

See also

   What is FWHM?

   Typical steps of the fwhm calibration

   FWHM pull-down menu

   FWHM module user screen

   Manual FWHM determination


What is FWHM?

FWHM = Full Width at Half Maximum

   FWHM is a typical parameter  of measured peaks frequently determined in several scientific fields, just as in  gamma-ray spectrometry.

   To manually characterise the width of a peak whose shape is essentially a Gaussian curve, one should consider first the height of the peak (which is the number of counts in the peak centroid channel) and calculate the width of the peak (in channels) at the half peak height ..

FWHM and resolution

   FWHM values at different energies are very important characteristics of a detector system. The  FWHM value at low energies represents the electronic noise of the detector and associated preamplifier. FWHM at high energies is mainly dependent on the quality of the Ge crystal. The smaller are these FWHM values the better is the system energy, the better resolution. Better resolution means that e.g. in the spectrum taken with better detector we see well-distinguishable two peaks instead of a doublet. For analytical purposes, the former case is much advantageous, because the uncertainty of an isolated peak area will be smaller in contrast with the latter case.

Energy dependency

   Semiconductor detectors has a well-defined peak energy - peak FWHM function:

      FWHM(E) = A + B*SQRT(E)

   that is, peak width varies by the square root of the peak energy. This function is widely used, and the same function with the two parameters A and B is used in the FWHM module.

See also

   Manual FWHM determination

   FWHM calibration module

   FWHM pull-down menu


Manual FWHM determination in Hypermet-PC

   In Hypermet-PC, there is only one situation when users should estimate the FWHM of peaks: during the rough peak width calibration in the Eval Module.

Steps to manually determine the FWHM of a peak:

1)  This process can be completed only in Main or Eval module. Switch to one of these modules to get proper results.

2)  If spectrum is not loaded, load it using File menu in the Main module.

3)  Ensure that the loaded spectrum is displayed with linear (and not logarithmic) scale. Switch to Linear display mode, by clicking on the green button captioned LOG on the bottom of the screen. If the LIN caption appears, you are in Linear display mode.

4)  If display is not in expanded mode, switch to this mode by selecting Display/Expand On/Off menu. (only in Main module).

5)  Locate the peak for which you want to determine the FWHM with the help of the rubber band.

6)  On the upper expanded window, place the channel cursor on the left side of the peak,  at half height.

7)  Use right arrow key on your keyboard for stepping precisely from the left side to the same height on the right side, meanwhile count the number of channels between the starting and ending point.

8)  Now you have the number of total channels at the half height: that is, FWHM.

See also

   What is FWHM?

   FWHM calibration module


Typical steps of the FWHM calibration

To create FWHM calibration:

1)  Measure some spectra  with different radioactive sources (possibly absolutely calibrated or home-made multi-gamma sources) at a given, preferred spectrometer setting. (e.g. 0 - 2 MeV / 8K)

2)  Load spectra and evaluate it in Eval module with two-point energy calibration. Then save fitting results in Hypermet-PC Short or Peaklist Report format or in Sampo-90 PTFformat.

3)  Start FWHM module with selecting Options / Qual. Assurance / FWHM menu.

4)  Load previously saved peaklist into FWHM module with Dataset / Load menu.

5)  Select nuclide(s) according to current peaklist (you can specify several nuclides at a time with the left mouse button while holding down <Shift> key.).

6)  Load all peaklists into FWHM module measured at the same spectrometer setting (repeat steps 4-5).

7)  If results are not applicable, change evaluation parameters (e.g. order of polynomial) by using Setting menu.

Note:

  FWHM module uses Nuclid.std file to offer list of nuclides at Step 5. If you could not find your preferred nuclide, quit Hypermet-PC and edit this file: put the data of isotopes into this file which you want to see in the list. Next time you start Hypermet-PC, changes take effect.

See also

    What is FWHM?

    FWHM calibration module

    FWHM pull-down menu

    FWHM module user screen


FWHM module pull-down menu

   With the FWHM (detector resolution) utility you can easily determine the resolution vs. energy function of your measurement system: load evaluated data by using Dataset / Load Sets if you are interested in resolution for peaks belonging to a specific isotope. If you want to involve all spectrum peaks into the FWHM curve determination, use Dataset / Load Each menu instead. In the former case, select isotopes involved in the actual measurement  by the left mouse button while holding down <Shift> key.

   If gamma line identification results are not acceptable, remove the entire dataset (press <PageDown> key to select and Dataset / Remove), then increase the identification threshold under Setting / Identification and reload  the dataset again.

File menu

   New

   Open

   Save

   Save as

   Return

Setting menu

    Identification

    Y-scale

    Residual

    Grid

Dataset menu

    Load Sets

    Load Each

    Remove

Report menu

    Short

    CSV

Help menu

See also

   What is FWHM ?

   FWHM calibration module

   Typical steps of the FWHM calibration

   FWHM module user screen


User screen of FWHM module

   In the FWHM module the middle of the screen is divided into two parts: lower and upper expanded window.

   In the upper window Hypermet-PC displays the peak width (detector resolution) versus the peak energy with the fitted FWHM curve. The fitted curve is drawn by a solid white line, while the standard deviation of the curve is indicated by a filled area with dark grey colour around the fitted curve. The data points loaded by Dataset / Load Sets or Load Each menu get individual colours, and are indicated with a cross, where the vertical line shows the standard deviation of the measured point (uncertainty in peak width).

   In the lower window the FWHM module shows the residuals (i.e. the difference between measured data and fitted curve) for individual data points in chi-square or keV scale. One standard deviation of data points around the fitted curve is indicated with a dark grey horizontal stripe in the middle of the residual window. Three times the standard deviation limit is indicated with two thin grey lines.

   Channel cursor can be moved by mouse or by pressing <LeftArrow> or <RightArrow> keys in both windows.

   Info pages contain detailed information about previously loaded and fitted datasets and about isotopes related with  the given dataset. To display the data belonging to a specific dataset, press <PageUp> or <PageDown> keys a few times.

   System specific data displayed on the first info page, as well as left and right boundaries of the interpolated region in keV, overall chi-square, coefficients of the fitted line with uncertainties in the parameters of the straight line. Note that the fitted curve is  linear if we use squared scale for the peak width (Y axis). FWHM module displays the resolution of your system at characteristic energies, such as 122.1 keV, 661.6 keV, and1332.5 keV.

   Dataset-specific data displayed on the following info pages are: the name of the peaklist file, number of identified gamma lines, isotopes related with  the dataset and corresponding chi-square values, if Load Sets menu was selected. If user involved all peaks in the peaklist by selecting Load Each menu, then the word each is displayed on the info page instead of the name of the relevant isotope.

See also:

   What is FWHM ?

   FWHM module

   Typical steps of the FWHM calibration

   FWHM module pull-down menu


File menu

(FWHM module)

   File menu manages resolution log files (which will contain all data necessary to reproduce the FWHM curve including data points, literary data of nuclides and displaying parameters) and to quit from FWHM module.

   Sub-menus in File menu make it possible to load a previously created FWHM log file, to save a newly created one or save it  with another file name. Using Return menu, you can leave FWHM module and return to Main module.

Available menus:

   New

   Open

   Save

   Save as

   Return

See also

   What is FWHM ?

   FWHM module pull-down menu


File / New menu

(FWHM module)

   Selecting this menu, FWHM module creates a new resolution log file, which will contain all data necessary to reproduce the FWHM curve including data points, literary data of nuclides and displaying parameters.

   Using this menu the previous FWHM log file will be closed and screen and info pages will be cleared. User can load new datasets (measured data points) to determinate the resolution of the system by which the measurement were taken by selecting Dataset / Load Sets or Load Each menu.

   After FWHM determination has successfully ended, user can save the newly created resolution log file by selecting the File / Save menu.

See also

   What is FWHM ?

   FWHM module pull-down menu


File / Open menu

(FWHM module)

  Selecting this menu, FWHM module opens a previously saved FWHM log file, which contains all data necessary to reproduce the whole FWHM curve including data points, literary data of nuclides and displaying parameters.

   After the user selected the file to open, previous FWHM fit will appear on the screen and detailed information will be shown on the info pages. User can then load new datasets, delete whole datasets or individual measurement points, change display parameters  and can save the modified resolution curve fit using File / Save or Save as menus. If you want to abandon changes, simply quit from the FWHM module and do not save the new fit to a disk file.

Note:

   Default file extension for resolution (FWHM) log files is FWH.

See also

   What is FWHM ?

   FWHM module pull-down menu


File / Save menu

(FWHM module)

   Selecting this menu, FWHM module saves the FWHM log file, which contains all data necessary to reproduce the FWHM curve including data points, literary data of nuclides and displaying parameters.

   If you loaded a previously saved FWHM file and made some modifications in the fit (e.g. adding new datasets, deleting data points or modifying  display parameters ), changes will be saved in the log file.

   If you newly created a fit, save it for a directory which serves as a common folder for a specific measurement system to store the quality assurance log files together.

   If you want to abandon changes, simply quit from the FWHM module and do not save the new fit to a disk file.

Note:

   Default file extension for resolution (FWHM) log files is FWH.

See also

   What is FWHM ?

   FWHM module pull-down menu


File / Save as menu

(FWHM module)

   Selecting this menu, FWHM module saves the FWHM log file, which contains all data necessary to reproduce the FWHM curve including data points, literary data of nuclides and displaying parameters.

   If you loaded a previously saved FWHM log file and made some modifications in the fit (e.g. adding new datasets, deleting data points or modifying  display parameters ), changes will be saved in another log file. This way user can make experiments with different settings.

   If you newly created a fit, this menu identical with the Save menu, that is it serves to save FWHM log files.

See also

   What is FWHM ?

   FWHM module pull-down menu


File / Return menu

(FWHM module)

   Selecting this menu the FWHM calibration module ends and control returns to the Main module.

   If you did not save the modified or newly created resolution log file, then Hypermet-PC remind you of saving the log file.

See also

   FWHM module pull-down menu


Setting menu

(FWHM module)

  By selecting Setting menu in the FWHM module, user can customise both the gamma line identification and the display properties of the fitted results.

Available menus:

    Identification: for setting the threshold value used in the gamma line identification

    Y scale: for setting the method used during fitting of the resolution curve

    Residual: for setting the type of residual data displayed in the lower quarter of the screen

    Grid: enables on disables the grid in the upper FWHM curve displaying window.

See also

   FWHM module pull-down menu


Identification menu
Setting / Identification menu

(FWHM module)

   When user select this menu, a pop-up window appears with two data input boxes. Changing these threshold values may affect the result of the FWHM curve fitting process.

Identification: FWHM module will search for matching of measured and literary peaks in the loaded datasets and in the Nuclid.std file. Peaks are treated as matched and will be involved in the fit if a measured peak is within the vicinity of a measured peak plus and minus this threshold channel value.

Acceptance of CHSQ: On the info page chi-square values belonging to isotopes will be indicated with green or red colour. The colour  depends on the value set here: if chi-square for an isotope is less than this threshold value, then it will be  green, otherwise  red.

Notes:

  - If the program could find only a few gamma lines for a multi-line gamma source, try to increase slightly the value of identification threshold. After you changed the threshold value, changes take effect only if you remove the whole dataset by using of Dataset / Remove menu and by loading it back by Dataset / Load Sets or Load Each.

See also

   FWHM module pull-down menu


Setting / Y-scale menu

(FWHM module)

   With the Setting / Y-scale menu, user can select the appropriate scale for displaying the width of fitted peaks.

Available menus:

Linear: Show the peak width (FWHM) on a linear Y scale.

Squared: Show the peak width on a squared Y scale.

Note:

   Because the peak width (FWHM) is linear function of the square root of the peak energy, it is common practice to display the peak width on a squared scale, therefore the curve  displays as a straight line.

See also

   FWHM module pull-down menu


Setting / Residual menu

(FWHM module)

   By selecting this menu, user can specify the type of the residual data displayed in the lower quarter of the screen. User can choose one from the three options below:

   None: switches off the residual window.

   Chi: switch residual window to display the differences between data points and the fitted curve in chi-square units. Scale is indicated with a dark grey stripe (fitted curve plus/minus one standard deviation) and with two dark grey lines (three standard deviation limit).

   Difference: switch residual window to display the differences between data points and the fitted curve in energy units (in keV). Scale is automatically normalised to the maximum deviation value and the zero difference from the fitted line is indicated with a horizontal dark grey line in the middle of the residual window.

See also

   FWHM module pull-down menu


Setting / Grid menu

(FWHM module)

   By selecting this menu, grid can be switched on or off for the upper resolution curve displaying window.

   The horizontal gridlines indicate the resolution at every 1 keV.

   Vertical gridlines are drawn at every 1 MeV energy value.

See also

   FWHM module pull-down menu


Dataset menu

(FWHM module)

   In FWHM module, Dataset serves to load measurement data from a saved peaklist file or to drop an entire dataset which is previously loaded.

Load Sets: User loads a peaklist and specifies nuclides present in  the spectrum. FWHM module will then identify the gamma lines for the specified nuclides and includes the relevant peaks in the FWHM fit.

Load Each: User loads a peaklist and includes all the peaks in the FWHM fit.

Remove: Drops a peaklist data and remove it from the actual FWHM fit. This menu is available only if user pressed the <PageUp> or <PageDown> keys to display the dataset data on the info page.

Notes:

 -  If the program could find only a few gamma lines for a multi-line gamma source, try to slightly increase the value of identification threshold. After you changed the threshold value, changes take effect only if you remove the whole dataset by using of Dataset / Remove menu and by loading it back by Dataset / Load Sets or Load Each.

 -  In general, peak fitting routine employed in Eval module fits the peak width for every region in the spectrum, and fixes the widths of peaks to a common value (if user switched off the Variable Peak Width Option). Thus peak widths are not varying within a region and using of the Load Each menu may cause incorrect results.

See also

   FWHM module pull-down menu


Report menu

(FWHM module)

   By selecting this menu, user can generate either a short or an extensive report of the actual resolution curve.

Available menus:

Short: generates a short report from the current fit in text format. Short report contains deviation and chi-square data for all data points, basic parameters of the fit, boundaries of the interpolated region, the parameters of the fitted line and the resolution of the system at characteristic energies. This report can be directly printed out.

CSV: generates an extensive report from the current fit in CSV format. The report file contains the same data as stored in the short format, plus the variance-covariance matrix of the fit. It is not advisable to directly print out this report, but this format ideal for processing it in spreadsheets programs.

See also

   FWHM module pull-down menu


Help menu (Nonlinearity module)
Help menu

(FWHM module)

This menu serves as fast link to the on-line help available for FWHM module.

See also

   What is FWHM ?

   FWHM module pull-down menu


Nuclide identification module
Nuclide ID module

   Nuclide identification module performs a very simply qualitative analysis from spectra taken with NAA (Neutron Activation Analysis) or PGAA (Prompt Gamma Activation Analysis) measurement methods.

   This module is  very fast, but usually overestimate the number of possible nuclides present in the measured spectra. This method combines statistical principles with arbitrary defined rules. It doesn't try to determine fine interactions between nuclides: treats nuclides as independent sources of radiation.

   Nuclide ID module may be a useful tool because it can keep  human intervention at a minimum during peak identifying process. At present, Nuclide ID has a library of more than 170 nuclides and 2700 gamma lines for NAA  and more than 80 elements and 5800 gamma lines for PGAA identification purposes.

See also

   Typical steps of nuclide identification

   Nuclide ID pull-down menu

   Nuclide ID algorithm

   Nuclide ID libraries


Nuclide ID module pull-down menu

  To load a peaklist which corresponds to the loaded spectrum in the Main module, use File / Load peaklist. To set the relevant analytical method, select Setting / Method. To perform an analysis, click on Analyze. To see results, select Report / Screen.

File menu

Setting menu

   Method

   Measurement

   Nuclides

   Parameters

   Report

   Load *.nus

   Save *.nus

Analyze menu

Report menu

Library menu

   Info

   Browse by energies

   Browse by nuclides

Help menu

See also

   Nuclide ID module

   Typical steps of nuclide identification

   Nuclide ID algorithm


Nuclide ID module algorithm

   Nuclide ID module performs a very simply qualitative analysis from spectra taken with NAA (Neutron Activation Analysis) or PGAA (Prompt Gamma Activation Analysis) measurement methods.

   The algorithm first tries to reduce the number of nuclides considered in the analysis. Nuclides can be excluded if NAA method is applied and the actual cooling time is larger than a pre-set value multiplied by the half-life of an isotope in question.

   Then searches all the literary peaks  in the nuclide library and tries to find the best match in the peaklist file. When the best match is found, a P value is computed. If this P value exceeds a pre-set threshold value, Nuclide ID stores the match in the internal database to create a report from them. Then a weighted Q value is computed for the given nuclide. The bigger Q value the higher the probability the nuclide can be found in the sample.

   Nuclide ID module performs escape peak determination, which is based on very simple principle: the algorithm searches only for a single escape peak for every measured peak, that is where the difference between two measured peaks is  511 keV. Then the algorithm computes the P value for the deviation as follows:

The whole Nuclide ID algorithm is the following:

(* nuclide identification *)

 apply half-life filtering

 for i= 1..nuclides

 (

   for j= 1..nuclide peaks

   (

     search for the closest spectrum peak

     compute Pij value for the  match

     if Pij > threshold, store the match

   )

   compute Q value for the nuclide

 )

 generate a list of nuclides sorted by Q values

 use a Q cut-off when display the list

(* escape peak identification *)

for i= 1..spectrum peaks

(

   search peaks near E=Ei-511 keV energy

   compute Pi value for Ei-E-511 deviation

   if Pi > threshold, then display the escape peak

)

See also

   Q and P value

   Computation of Q and P values

   Typical steps of nuclide identification

   Nuclide ID pull-down menu

   Nuclide ID libraries


File menu

(Nuclide ID module)

   By selecting the File menu in Nuclide ID module, user can load a peaklist file to analyse which was saved in the Eval module and can leave Nuclide ID module.

Load peaklist: loads a peaklist to analyse.

Load EFF file: loads a previously created efficiency file for analysis (available only for PGAA method).

Return: quits Nuclide ID module.

Notes:

  -  Peaklist file must correspond to the spectrum file which is loaded in Main module before you started Nuclide ID.

  -  By selecting Return menu, Nuclide ID module immediately ends. If user omitted to save report file about the result of nuclide identification process, result data will be lost.

See also

   Nuclide ID pull-down menu


Setting menu

(Nuclide ID module)

   By selecting this menu, user can customise the nuclide identification process and the content of the report file. It is possible to save all the parameters to a disk file and load them back later to speed up the configuring of the identification process.

Available menus

   Method: toggles between NAA and PGAA (Instrumental neutron and Prompt-gamma activation analysis) method

   Measurement: Sets measurement parameters for NAA method

   Nuclides: Customises the nuclide range involved during the analysis

   Parameters: Sets the parameters of the identification algorithm.

   Report: Enables or disables specific sections of the report file

   Load *.nus: Loads a previously saved setting file

   Save *.nus: Saves parameters set in the Nuclide ID module

See also

   Nuclide ID algorithm

   Nuclide ID pull-down menu


Setting / Method menu

(Nuclide ID module)

   By selecting this menu, user can select the analytical method by which the measurement was taken.

Available menus

NAA: sets the analytical method to NAA (Instrumental or Reactor-neutron Activation Analysis) method. By using this identification mode, Nuclide ID filters out some of the nuclides by their half-life and uses the decay gamma library to search for nuclides in the spectrum.

PGAA: sets the analytical method to PGAA (Prompt-gamma Activation Analysis) method. By using this identification mode, Nuclide ID will use the prompt-gamma library to search for chemical elements in the spectrum.

See also

   Nuclide ID pull-down menu


Setting / Measurement menu

(Nuclide ID module)

   By selecting this menu, user can set parameters of NAA measurements in the appearing pop-up window. At this stage of the analysis, only the Cooling time parameter should be set in order to apply a proper half-life filtering of nuclides. User can place comments in the report file by filling the Sample code field.

Note:

   This menu is not applicable the Prompt-gamma Activation Analysis method.

See also

   Half-life filtering

   NAA measurement parameters setting window

   Nuclide ID pull-down menu


Setting / Nuclides menu

(Nuclide ID module)

   By selecting this menu, the nuclide selection window appears where user can simply customise the range of nuclides or elements involved in the analytical process. The range of nuclides can be saved into a disk file, therefore it is possible to create different nuclide compounds for specific purposes. However, this manual filtering of nuclides necessary only if a disturbing nuclide (or element) appears in the analytical results.

Note:

   By using NAA method, algorithm searches for nuclides, while at PGAA method the search is made for chemical elements.

See also

   Nuclide selection window

   Nuclide ID pull-down menu


Setting / Parameters menu

(Nuclide ID module)

   With the selection of this menu, user can specify values applied during the nuclide identification algorithm in the appearing Nuclide ID parameter window.

   Adjustable parameters are energy range of the evaluation, additive peak position uncertainty, limits for random sum peak test, half-life exclusion and peak matching limit.

See also

   Nuclide ID parameter window

   Nuclide ID algorithm

   Nuclide ID pull-down menu


Setting / Report menu

(Nuclide ID module)

   User can independently enable or disable various sections of the Nuclide ID report file. Disabling of a section may be necessary in some cases when the detailed report file would be too long, especially in PGAA analysis.

   By selecting of this menu, a Report customising window appears, where user can simply enable or disable different report sections.

See also

   Report customising window

   Nuclide ID pull-down menu


Load *.nus menu

(Nuclide ID module)

   Selecting this menu, a file loading window appears, by which user can specify a Nuclide ID setting file (a file with NUS extension). All the parameters set at the time when user saved the parameters with Setting / Save *.nus menu will be restored, including the range of nuclides. Only one parameter, the analytical method may not be restored this way. To switch between analytical methods, use Setting / Method menu.

See also

   Nuclide ID pull-down menu


Save *.nus menu

(Nuclide ID module)

   Selecting this menu, a file saving window appears, by which user can specify the name of a new Nuclide ID setting file.. The file with NUS extension will contain all analysis parameters including the range of nuclides (or elements). These parameters can be reloaded later with the help of the Setting / Load menu.

See also

   Nuclide ID pull-down menu


Analyze menu

(Nuclide ID module)

   By selecting this menu, Nuclide identification algorithm starts to determine the nuclides most probably  present in the sample. During the identification process, the examined nuclide appears in the upper right corner of the screen. If identification completed, user should select the Report / Screen menu to display the results.

See also

   Nuclide ID algorithm

   Nuclide ID pull-down menu


Report menu

(Nuclide ID module)

   After a successful identification, user should display the results by selecting Report menu.

Available menus

File: Saves the results in a simple text file

Screen: Shows the results on a scrollable text mode screen

Printer: Prints the results directly to the pre-set printer port (parallel port).

See also

   Content of Nuclide ID report file

   Printing from Hypermet-PC

   Nuclide ID pull-down menu


Library menu

(Nuclide ID module)

   By selecting Library menu, user can get information about the gamma library loaded for the actual analytical method (NAA or PGAA).

Available menus:

   Info: serves basic information about the library

   Browse by energies: let the user to browse the library by gamma energy

   Browse by nuclides: let the user to browse the library by mass number of nuclides

See also

   Nuclide ID pull-down menu


Library / Info menu

(Nuclide ID module)

   If user selects this menu, a pop-up window appears which provides basic information about the library actually loaded: it displays the number of nuclides and gamma lines, as well as the minimum and maximum mass number and atomic number of the involved nuclides (or elements).

   You can change the library in Nuclide ID module by changing the applied analytical method under the Setting / Method menu. Nuclide ID module automatically loads the appropriate library necessary for the evaluation of the actual spectrum.

Note

   To list the detailed content of the library by nuclides or by gamma line energies, use Library / Browse by nuclides or Library / Browse by energies menu, respectively.

See also

   Nuclide ID pull-down menu


Library / Browse by Energy menu

(Nuclide ID module)

   By selecting this menu, a text mode result browser window appears which displays the contents of the actually loaded nuclide library. The list of gamma lines is ordered by energy.

   To close the browser window, press <Esc> key or click on the Return menu with the mouse.

See also

   Result Browser window

   Nuclide ID pull-down menu


Library / Browse by Nuclides menu

(Nuclide ID module)

   By selecting this menu, a text mode result browser window appears which displays the contents of the actually loaded nuclide library. The list of nuclides (or elements if user chose the PGAA method) is ordered by mass number.

   To close the browser window, press <Esc> key or click on the Return menu with the mouse.

See also

   Result Browser window

   Nuclide ID pull-down menu


Help menu

(Nuclide ID module)

  This menu serves to invoke the on-line Help facility for Nuclide ID module.

See also

   Nuclide ID pull-down menu


User screen of Nuclide ID module

   At this stage of Nuclide ID module, detailed information are not shown on the graphical screen about the results of nuclide identification. The screen content is identical with that of the Main module. However, user can browse the results on the text mode screen by using Report / Screen menu.

See also

   Typical steps of nuclide identification


Typical steps of nuclide identification

For a qualitative nuclide identification, user should follow the steps below.

1)  Evaluate your spectrum with Eval module and save a report file in short or peaklist format (see spectrum evaluation).

2)  Start Nuclide ID module by selecting Options / Nuclide ID menu (spectrum file to be evaluated must be loaded using the Load menu of Main module).

3)  Load previously saved report files using File / Open peaklist menu.

4)  Set measurement method under Setting / Method menu. User can choose from NAA or PGAA methods (NAA is the default).

5)  In the case of NAA method, set the Cooling time parameter using Setting / Measurement menu. Write a descriptive text into the Sample code field. Content of this field will appear in Nuclide ID report file.

6)  Start the analysis by selecting  Analyze. In the upper right corner of the screen nuclide actually analysed appears.

7)  After completing analysis, you can revise results by selecting Report / Screen menu.

8)  If results are not acceptable, try to change parameters under Setting menu (e.g. remove disturbing nuclides).

See also

    Nuclide ID algorithm

    Nuclide ID Module


Q and P value (Nuclide ID module)
Q and P value

   Q value is a dimensionless numeric value. It belongs to individual nuclides and used to sort them into a list based on their significance in the irradiated sample.

We emphasise that

1)  Q value is a simple but useful  characteristic of the significance of the given nuclide;

2)  Nuclide ID algorithm do not match intensities of peaks yet, but only  measured and literary peak energies.

Computation of Q-value:

   Q-value is a weighted and normalised sum of P-values. Weighting factor is the square of the normalised peak intensity (strongest lines intensity is 1.0).

   Q value is normalised, so its range extends from zero (nuclide is not significant) to 1.0 (nuclide is highly probable to be in the sample).

Computation of P-value:

   P value is a numeric value which describes the matching of an literary and the nearest measured peak. A P value is computed from peak energies and uncertainties assuming normal distribution of peak positions around their literary peak position value. P extends from zero (matching of literary and the nearest measured peak is highly improbable) to 1.0 (matching is highly probable).

See also

   Q list of nuclides

   Equations for Q and P

   Nuclide ID algorithm


Computation of Q and P values

Qi = SUMj(Pij*Iij^2) / SUMj(Iij^2)    j = 1..n

where

    Qi  Q-value of i-th nuclide (significance in sample)

    Pij P value of i-th nuclides j-th gamma line

    Iij normalised intensity for i-th nuclides j-th gamma line (0.0 .. 1.0)

    n   number of gamma lines for -th nuclide

Pij = 2*(1.0 -PHI0( DE/SIG ))    and

SIG = (Sm^2 +Sl^2 +Sa^2)

where

    Pij  P value of I-th nuclides j-th gamma line

    PHI0 distribution function of standardised normal distribution

    DE   distance of literary and measured peak

    SIG  combined uncertainty of matching

    Sm   position uncertainty of measured peak

    Sl   position uncertainty of literary peak

    Sa   additive position uncertainty

See also

   Q list of nuclides

   Description of Q and P values

   Nuclide ID algorithm


Additive peak position uncertainty

   Nuclide ID routine uses literary and fitted peak energies and their  uncertainties to identify a measured peak and to estimate the probability of this identification. In practice, it was necessary to use an additive error component for accurate match detection, which is a linear function of peak energy.  These  error components are then summed quadratically  forming an overall error which is finally used for peak matching.

Suggested values:

- for NAA : 0.5 keV at 1 MeV, 1 keV at 10 MeV (better spectrometers with predetermined nonlinearity function can use  smaller additive uncertainty values, e.g. 0.1keV and 0.1 keV, respectively);

- for PGAA: 1 keV at 1keV and 1-1.5 keV at 10 MeV (because of larger literary peak uncertainties)

Note: you can set the additive peak position uncertainty to zero at both specification points, so program will use 'pure' uncertainties derived from the real spectrum.  This is acceptable if your measuring system is calibrated with high precision and accuracy (and nonlinearity correction is used during peaklist generation).

See also

   Q list of nuclides

   Description of Q and P values

   Equations for Q and P

   Nuclide ID algorithm


Half-life filtering

(Nuclide ID module)

   Nuclide ID module tries to reduce the number of nuclides involved in the analytical process. To achieve this it rejects nuclides with half-lives  much smaller than the cooling time (e.g. if the cooling time is larger than 20 times the half-life)).

   Not every nuclide can be filtered out  by its half-life because of their complicated decay schemes. We use decay categories from [FDEC89], where the nuclides are classified by their decay type into several main and sub-groups. Some of the decay schemes can be treated with simple half-life comparison while in other cases it is possible to take into account the half-life of mother nuclide. In a few cases, nuclides can not be excluded by their half-life at all.

   If a specific nuclide can be excluded by cooling time, Nuclide ID module temporarily removes it from the candidates and lists the excluded nuclides in the Nuclide ID report file.

See also

   Setting NAA measurement parameters

   Nuclide ID algorithm


Content of Nuclide ID report file

   Nuclide ID module may produce an extensive report about the analytical results. The report contains a header and several sections which may be independently enabled or disabled.

Header content

  - Date and time for the analysis

  - File name of the spectrum and peaklist files

  - Header text of the binary spectrum file

  - Corrections applied in the peaklist file

  - Sample code field given by the user

  - Analytical method (NAA / PGAA)

  - Nuclides excluded by user

Report sections

  - Q list of nuclides

  - Nuclides excluded by half-life

  - Nuclides found

  - Unidentified peaks

  - Escape peaks

  - Nuclides by peaks

See also

   Nuclide ID algorithm


Q list of nuclides (Nuclide ID report)
Q list of nuclides

(Nuclide ID report section)

   Q list of nuclides means a nuclide list sorted by  Q-values. In general, the higher the Q-value, the more probable the nuclide can be found in the sample.

See also

  Description of Q and P values

  Report customising window

  Nuclide ID algorithm


Nuclides excluded by half-life

(Nuclide ID report section)

   Within this section, Nuclide ID module lists all the nuclides excluded by the specified cooling time for the sample and the half-life of the actual nuclide.

Example:

Cooling time was          1 h

Nuclides excluded if  Tcool > T(1/2)*20  and decay code=1,4B,6,7B or in special mother-daughter decay case. Excluded nuclides:

   Nuclide  T(1/2)  T(1/2)*20 Decay

            [sec]   [sec]      Code

-----------------------------------

...

5.  24mNa    0.02    0.40       1

6.   28Al  134.40 2688.00       1

7.  38mCl    0.71   14.30       1

8.  46mSc   18.75  375.00       1

See also

   Half-life filtering

   Nuclide ID report file content

   Nuclide ID algorithm


Nuclides found (Nuclide ID report)
Nuclides found

(Nuclide ID report section)

  This section contains all data for that nuclides, which has at least one matched peak with P greater than the Peak matching limit parameter. The nuclides are sorted by mass number and atomic number.

   The report contains Q value for each nuclide and all found peaks whose P value is higher than the Peak matching limit parameter. The report contains the relative intensity, measured and literary energy, P value and the energy distance per total peak position uncertainty value for each peak.

Note:

  - To set Peak matching limit parameter, use Setting / Parameters menu.

Example:

152Eu peaks  Q(152Eu)=0.965  T(1/2)=13.54y

             DecayCode: 4B

Spe.|Libr.|Rel. |Meas.  |Libr.  |P(ij) |dE/Sig |

pk #|pk # |Int. |       |E[keV] |E[keV]|       |

----+-----+-----+-------+-------+------+-------+

 1. |  1  |1.000| 121.80| 121.78| 0.97 | 0.043 |

10. |  2  |0.937| 344.28| 344.28| 1.00 | 0.000 |

37. |  3  |0.735|1408.02|1408.01| 0.98 | 0.021 |

...

  In PGAA mode, a new column appears for every library peak: the approximated element weight contained in the sample.

See also

   Description of Q and P values

   Nuclide ID report file content

   Nuclide ID algorithm


Approximate element weight

(Nuclide ID module, PGAA method)

   In PGAA mode, a new column appears in the Nuclides found report section for every library peak: the approximated element weight (m*) contained in the sample. It is reported only if the appropriate Efficiency file is loaded with File / Load EFF File menu. The calculation of the approximated weight is as follows:

 m* = Area*Molwt / (Eff*Flux*AbsInt*LiveTime*Crossec*Nav)

where

   Area: peak area

   Molwt: relative atomic mass of the given element

   Eff: detector efficiency at the energy of the peak

   Flux: thermal flux during measurement

   AbsInt: absolute intensity of the library peak

   LiveTime: duration of the measurement

   Crossec: thermal neutron cross section for the given element.

   Nav: Avogadro constant

Note:

  User may apply absolute or relative detector efficiency function for computing m* value. In the former case a real element weight is computed, while in the latter case only an approximate value is given.

See also

   Description of Q and P values

   Nuclide ID report file content

   Nuclide ID algorithm


Unidentified peaks (Nuclide ID report)
Unidentified peaks

(Nuclide ID report section)

This section contains peaks, to which Nuclide ID algorithm could not assign a literary peak from the current nuclide library. The listed details: serial number, energy, area, area uncertainty of the peak.

Example:

  Spe.pk     Energy     Area   Unc. of Area

    #         [keV]     [cnt]       %

-------------------------------------------

1.  11.      367.927     349     24.05 %

2.  12.      385.765     191     21.30 %

...

See also

   Description of Q and P values

   Nuclide ID report file content

   Nuclide ID algorithm


Escape peaks (Nuclide ID report)
Escape peaks

(Nuclide ID report section)

   Nuclide ID module lists the assumed escape peaks in this section. In the list of escape peaks the serial number and the energy of the escape and full-energy peak and the P value for the match are detailed.

Example:

ESCpeak ESCpeak FEpeak  FEpeak   P(match)

    #   E [keV]   #     E [keV]

------------------------------------------------

1.  23  1127.67  51    1642.379  0.247

2.  23  1127.67  50    1639.786  0.726

3.  24  1131.24  50    1639.786  0.105

...

See also

   Description of Q and P values

   Nuclide ID report file content

   Nuclide ID algorithm


Nuclides by peaks (Nuclide ID report)
Nuclides by peaks

(Nuclide ID report section)

In this section the found nuclides are listed by measured peaks. The listed data are: energy, area and area uncertainty of measured peaks, and isotope and characteristic gamma line energy found for that peak.

Example:

Spe.|   Energy

pk.#|    [keV]

----+--------------------------------

...

34.  818.035 keV,   20424 cnt +-0.80%

      P(110mAg # 9)=0.993 [E= 818.03]

      P( 110Ag # 5)=0.755 [E= 818.20]

      P( 151Pm #56)=0.527 [E= 817.70]

      P( 151Pm #77)=0.527 [E= 817.70]

      P(111mPd #58)=0.353 [E= 817.00]

      P(116mIn # 4)=0.209 [E= 818.70]

      P( 111Pd #56)=0.168 [E= 816.50]

...

43. 1334.338 keV,     262 cnt +-13.30%

      P(110mAg #18)=0.996 [E=1334.34]

      P(   52V # 2)=0.187 [E=1333.62]

      Escape of pk#57. P(match)=0.25

...

See also

   Description of Q and P values

   Nuclide ID report file content

   Nuclide ID algorithm


Keyboard commands

   You can access Hypermet-PC commands using keyboard or mouse. Sometimes it is necessary to use mouse and keyboard at the same time.

   We offer a keyboard command list below grouped by their accessibility.

General applicable keyboard commands:

key         action

-----      -----------------------

Left       Move cursor to previous channel

Right      Move cursor to next channel

Home       Move cursor and rubber band to the first channel

Alt+Left   Move rubber band to left

Alt+Right  Move rubber band to right

Alt+Up     Move rubber band to up

Alt+Down   Move rubber band to down

Ctrl+Left  Reduce rubber band horizontally

Ctrl+Right Enlarge rubber band horizontally

Ctrl+Up    Enlarge rubber band vertically

Ctrl+Down  Collapse rubber band vertically

 F1        Invoke context-sensitive help

Alt+P      Graphic screen dump to BMP file

In the Main and Eval module:

 Up        Increase of vertical scale

           in upper expanded window

 Down      Decrease of vertical scale

           in upper expanded window

 Del       Deletes actual ROI (only if channel cursor is in a ROI)

In the Eval module:

Keyboard commands applicable if Logbook is open:

Gray+      Go to next region

Gray-      Go to previous region

  <        Select previous channel for refit (same as sweeping with the right mouse button)

  >        Select previous channel for refit

Additionally, if actual region has refit(s):

  [        Go to previous alternative fit (refit)

  ]        Go to next alternative fit (refit)

Keyboard commands to use together with mouse:

 key   mouse   action

-----  -----  -------------------------------

 Ctrl   Left   Selects more elements from a list at a time

See also

 using mouse


Answers to frequently asked questions (FAQ)

   We collect some typical questions below grouped by categories. With clicking on appropriate 'Q' (question) symbol, you can read answers for that questions.

General

Q: System requirements of Hypermet-PC

Fitting of spectrum peaks

Q: Which are the typical steps of spectrum fitting process?

Q: I set proper energy calibration in a spectrum. Next time I loaded the same spectrum, I find the energy calibration is missing. Whats wrong?

Q: How can I initiate a manual peak fit?

Energy calibration

Q: How can I ensure accurate energy calibration of fitted peaks?

Q: How can nonlinearity curve improve precision of energy calibration?

Nonlinearity curve fitting

Q: What is nonlinearity?

Q: Which are the typical steps of nonlinearity curve creating?

Efficiency curve fitting

Q: What is efficiency?

Q: Which are the typical steps of spectrum fitting process?

FWHM calibration

Q: What is FWHM?

Q: Which are the typical steps of FWHM fitting process?

Nuclide identification

Q: Which are the typical steps of nuclide identification?

Printing

Q: Printing does not work under DOS. What went wrong?

Q: Printing does not work under Windows. What went wrong?


Printing does not work under DOS

   Consider this troubleshooting section if printing problem occurs and Windows is not running.

1) Specify the correct LTP port

- Be sure you specified the appropriate parallel (LPT) port in HYPC.INI file under PRINTING section. For example, if your printer is attached to LPT1 (in the most  cases this is true), then you should set PrinterPort variable to 1. If you modified HYPC.INI, do not forget to quit and restart Hypermet-PC in order the changes take effect.

- Be sure you are editing the appropriate HYPC.INI file: the value will be read in from that HYPC.INI file which is placed in the directory where you have started HYPC.EXE, or if you have not got multiple HYPC.INI files, then it is placed in the directory where HYPC.EXE resides.

Now try again to print from Hypermet-PC.

If printing does not work,

2) Check printer connection

- Be sure the printer is attached to the appropriate parallel port which you have specified, it is connected to the power and it is switched  on-line.

- Quit to DOS and type the command  similar to the following (this example is for LPT1 - if you are using another port, replace the port number with the right one):

  COPY C:\AUTOEXEC.BAT LPT1:

     This prints a simple text file on LPT1. Sometimes it is necessary to send this file two times to the printer to get correct result. If printer does not print after the second try, it means that there is no proper connection between the computer and the printer. Check the plugs, cables, turn off and on printers and try again. If printer does not work, you must ask for a computer expert to explore the source of error.


Printing does not work under Windows

   If Hypermet-PC does not print under MS-Windows, refer Windows Help or other documentation to resolve printing problem.


Typical steps of a spectrum fitting process

1)  Load spectrum in the Main module with File / Open menu.

2)  Select Eval to initiate spectrum fitting. Eval module appears.

3)  If you have previously saved *.SET file for the spectrum, load it with Setting / Load *.SET menu. Please note that Hypermet-PC needs at least a rough peak width calibration before fitting.

4)  Select Fit menu and set Auto checkbox. Pressing OK Hypermet-PC automatically starts  evaluating all of remaining regions in your spectrum. If spectrum  analysis completed, 'No (more) peaks found' message appears and fitting results disappear from screen.

5)  To revise your fitting results, select Logbook / Region menu and double-click on a region in the region list. Fitting details of selected region appears. To jump to a next region, press the grey '+' key on keyboard, while the previous region can be reached by pressing grey '-' key. To display individual peak data, press PgUp / PgDn keys. If you click outside of upper expanded window, fitting results disappear again.

See also

    Spectrum evaluation with Hypermet-PC

    Manual correction of bad fits


Manual correction of bad fits (Eval module)
Manual correction of bad fits

   There are some typical symptoms when user want to change properties of fit. Most of them can be corrected with little user interaction.

Symptoms of bad fit

- Hypermet-PC couldn't find a small peak around big peaks.

- Peaks seem to 'sit down' below real background

- Peak has a large tail on the right-side; this fitted with multiplet

Most frequently used corrections:

 - setting wider background boundaries

 - insert a new peak at a specific channel

 - delete a peak from a region

 - delete a whole region

 - perform a fit with Variable Peak Width Option

 - fine-tuning the fitting parameters


Setting a wider background

   When the automatically chosen background boundaries (that is, the left and right channel of a region)  seem to be inappropriate, user may define a wider background applying the following steps:

 1) If fitting results are not displayed on the screen, then open the Logbook by selecting the Logbook / Region menu and double-clicking on the faulty region.

 2) Move the mouse to the left side of the wider region. Press and hold down the right mouse button while sweeping over the whole region from left to right. The white points of the channel counts become blue, indicating the extension of the new region.

 3) Select Fit menu to re-fit this region. The fitting pop-up window appears. Clear the Auto, ROI and Peak integration check boxes and set the Fix check box. This prevents the fitting algorithm to modify the region boundaries.

 4) Press OK to initiate the refit.

Note

  Because Hypermet-PC fitting algorithm retains the previously found peaks in consecutive fits, therefore if user wants to eliminate a peak at the same time when a wider background is set, then first the peak(s) must be deleted (by Logbook / Peak menu and Delete button), and afterwards the re-fit may be achieved on a wider background.


Insert a new peak into a region

   Sometimes the user suspects that the Hypermet-PC fitting algorithm could not detect a peak in a specific region. In these cases it is possible that the user inserts an unevaluated peak into that region following next steps:

 1) If fitting results are not displayed on the screen, then open the Logbook by selecting the Logbook / Region menu and double-clicking on the faulty region.

 2) Place the channel cursor to that position where you suspect a missing peak. This task may be accomplished much easier if the residual window is switched on (pressing SPECT green button at the bottom of the screen).

 3) Select Logbook / Peak menu. The peak manipulation window appears.

 4) Press Insert button. A peak insertion window appears. Type in the appropriate peak position value with estimated uncertainty information. (The default position value is obtained from the position of the cursor.)

 5) Select Fit menu to re-fit this region. The fitting pop-up window appears. Press OK to initiate the refit.

Note

  If the area of the newly inserted peak turns out to be not significant (that is, the uncertainty of the peak area is greater than the area itself) then the peak is deleted from the region and does not appear on the screen.


Delete a peak from a region

   User sometimes may observe spurious peaks after a fit: for example when user judge that only a single peak can be found in the region, but Hypermet-PC fitted it with a multiplet. These multiplets may appear, especially when the peak is significantly wider than the assumed FWHM value (from the two-point peak width calibration).

   Because Hypermet-PC fitting algorithm retains the previously found peaks in consecutive fits, therefore user should delete a superfluous peak from the region before performing a refit with modified fitting parameters (e.g. with modified peak width calibration).

   After the modifications have been made in fitting parameters and user  deleted a specific peak from the fitted region, do the followings:

1) If fitting results are not displayed on the screen,  open the Logbook by selecting the Logbook / Region menu and double-clicking on the faulty region.

 2) Place the channel cursor closest to the peak to be deleted.

 3) Select Logbook / Peak menu. The peak manipulation window appears. Select the peak for deletion (the peak selected by default is the closest to the channel cursor).

 4) Click on Delete button. Now the selected peak is deleted from the logbook.

 5) Select Fit menu to re-fit this region. The fitting pop-up window appears. Press OK to initiate the refit.

Note

  If Hypermet-PC fitting algorithm finds that a peak must be inserted at the position where the user previously deleted a peak, it will re-insert a peak in order to reduce overall chi-square.


Delete a whole region

 In spite of the sophisticated fitting algorithm involved in Hypermet-PC, there may occur completely erroneous fits when solving very complicated problems. The main reasons of this situation may be:

- the initial parameters are very far from the real ones (especially true if user has been set a bad FWHM calibration)

- the degree of freedom is a very small number (e.g. when user switches on the Variable Peak Width Option)

- the shape of the background can not be determined (if peaks are heavily convoluted in the region)

- when the FWHM of peaks is varying widely within the same region (e.g. for neighbours of  the 511 keV annihilation peak)

   In this cases the proper method for improving the fit is: complete removing of fitted peaks (note that all the peaks whenever fitted will be kept in consecutive refits - and this is true for faulty peaks) by deleting the entire region, change initial fitting parameters and perform a refit.

To delete a whole region:

 1) Select Logbook / Region menu. The region manipulation window appears. Select the region for deletion.

 2) Click on Delete  button. Now the selected peak is deleted from the logbook.

Note

   It is possible to delete only a specified peak from a region.


Using the Variable Peak Width Option

   Hypermet-PC normally fits all peaks found in a region with the same FWHM value. The common peak width is fitted based on the rough FWHM calibration as initial value and the constraints specified under Setting / Fine Tune / Peak menu.

   In rare cases overlapping peaks may be observed with considerably different peak width. Hypermet-PC supplies a unique Variable Peak Width Option to properly fit these multiplets.

   Using this option it is possible to set up the algorithm to perform a fit with variable peak width for every peak in the region - that is, the FWHM value is fitted for every peak individually. This feature may resolve a multiplet even if a peak is overlap with the 511 keV annihilation peak (which appears with a considerable wider peak width).

To switch on the Variable Peak Width Option:

 1) Select Setting / Fine Tune / Peak menu. A peak shape setting pop-up window appears.

 2) Select the radiobutton Variable in the frame captioned Gaussian width. The option is now switched on.

 3) Click on OK press button to close the window.

Notes

- To switch off this option, select the Common radiobutton.

- Use this option with distinguished caution. Apply it only if you are absolutely sure the actual region has peaks with different FWHM. Note that Hypermet-PC can perform a proper fit on peaks which has basically Gaussian shape (e.g. X-ray peaks can not be properly resolved by the program). The fitting algorithm may provide erroneous results due to the decreased number of free parameters included in the fit.


Fine-tuning fitting parameters

Initial Peak Width Estimation: Only rough peak width estimation is required for automatic analysis of spectra. Realistic peak width values are necessary for the peak search routine.

See also

   Using the Variable Peak Width Option


Couldn't find a small peak symptom
'Couldn't find a small peak' symptom

There may be several reasons why Hypermet-PC couldn't find a small peak during spectrum evaluation:

- Peak area is not significant. This is the most common case: the peak search routine does not exceed the detection threshold. There is two threshold value in Hypermet-PC: one for general peak search, and a second one for searching in the residual. These values can be set at Setting / Fine Tune / Sigma menu. If changed values does not produce expected results, it is possible to inserting a peak manually at a specific position.

- Fwhm calibration is bad. Replace the existing rough peak with calibration with a new one.


Sit down symptom of fits
'Sit down' symptom of fits

   If peaks seem to 'sit down' below real background (fitted background line and the down end of peaks are below the real background), this may happen because:

- Your approximate width calibration is faulty (you have specified larger FWHM for peaks than the real value) or

- Distance between peak width calibration points are too small. This results in poor extrapolation of peak width at the far end of the spectrum.

Solution:

   Create new FWHM calibration


Multiplet fit with large right-side tail symptom

  Sometimes only one solution left out to correct this type of bad fit: replace the fit created by Hypermet-PC with a very rough peak integration function. We emphasise that this phenomenon occurs only if your detector analyser system produces extreme wide peaks due to extreme high counting rate and/or improper pile-up rejector operation.

Solution:

   Peak integration


Missing energy calibration

   If you want to learn the energy calibration concept of Hypermet-PC, see energy calibration.

   If you have set an energy (and peak width) calibration in Eval module, save it into a *.SET file for later use. We suggest that a *.SET file be saved to the directory of original spectrum. Next time you load your spectrum and start Eval module, simply load your relevant *.SET file and your calibration settings will be restored. This procedure is especially advantageous  when no or incomplete calibration data is attached to the spectrum  (e.g. spectra in ASCII format)

  If your calibration data settings are abruptly changed on a mysterious way, see details of overwriting calibration data.

Note:

   If you forget to save your calibration file, it can be restored manually.

See also

   Overwriting of calibration data

   Setting files (*.SET)


Manual peak fitting
Manual peak fits

   In Hypermet-PC, the process of peak fitting is fully automated. To learn more about the implemented peak fitting method , see: spectrum evaluation with Hypermet-PC.

   If  a region is fitted, it is possible: to delete the whole region, to delete a peak from or to insert a peak to the region and refit the whole region. Moreover, user can select 'best' refit from the refits on a region (and delete unnecessary regions ). See details in manual correction of bad fits.

    In special circumstances you may use peak integration instead of Hypermet-PC's standard fitting routine.


Peak integration (Eval module)
Peak integration

   In Hypermet-PC,  the standard peak fitting process is fully automated. However, there is a possibility to select manually a region of channels and initiate  a very simple peak integration procedure (similar to the so called trapezoid peak integration method). Peak integration works only on  regions where a normal fits were also performed.

Steps to perform a peak integration:

1) Load a spectrum in main menu and enter Eval module..

2) Make a normal fit on selected region of channels (or if you have a log file which is previously created, use Logbook / Region to display a specific region).

3) Select a region by sweeping with mouse over channels while you are pressing RIGHT mouse button. Channels selected for peak integration will turn  to blue.

4) Select Fit menu and click on 'Peak integration' check box.

5) Push OK button to initiate a special peak integration mode  on selected channels.

   During fit, Hypermet-PC calculates  averages of  3 - 3 channel contents at both ends of a selected region and draw a linear background between these two points. Afterwards,  channel contents between first and last selected channels will be summed up considering a linear background. The new fit  will be displayed in grey over normal fitting results.

This special peak integration module is provided for convenience to evaluate irregular peaks resulting from spectrometer malfunction (inadequate pile-up rejection, unexpected shift, etc.) .

See also

   Spectrum evaluation with Hypermet-PC

   Typical steps of spectrum fitting process


Rough FWHM calibration before fitting

   Before starting spectrum evaluation, Hypermet-PC must have at least a rough peak width (FWHM) calibration.

Steps to set rough FWHM calibration:

1)  In Eval module, search for a clear, single and intense peak in the first quarter of the spectrum. Locate it to the upper expanded window by dragging and re-sizing rubber band in the lower half of the screen (lower expanded window).

2)  Switch to LIN spectrum display mode with green LOG button (if you are using Hypermet-PC in logarithmic display mode).

3)  Estimate the width of peak at its half maximum (how many channels fall between half-height channel contents).

4)  Selecting Fit menu a 'Region to Fit' window appears. Write in estimated peak width value into Width input box.

5)  Clear Auto, Fix and ROI check boxes.

6)  Press OK to initiate a fit  in the region displayed in upper expanded window.

7)  After the fit, place channel cursor to fitted peak (just clicking on it in the upper half) and select Setting / Calibr menu. Hypermet-PC calibration window now appears.

8)  Select 'Fitted position' energy calibration mode and press the uppermost  radiobutton. Hypermet-PC now automatically records the position and half-width of this peak as the first point for the rough FWHM calibration line.

9)  To set a second point for peak width calibration line, select a clear peak in the last quarter of spectrum and repeat the process described above. Be sure to press appropriate radiobutton in Calibration window (positioned close to second half-width point).

See also

   Calibration window

   Calibr menu


Installing mouse on your computer

   Hypermet-PC is a mouse oriented DOS program, so the usage of mouse is essential for efficient work.

   For using mouse under DOS or under Windows 3.x DOS box, you must supply appropriate DOS mouse driver program (mouse handler software element). (If Hypermet-PC runs under Windows95, the operating system will provide an appropriate mouse driver automatically.)

   If arrow-shaped mouse cursor does not appear after starting Hypermet-PC, this means that mouse driver is not present. To install a mouse driver for DOS or for Windows 3.x DOS box, user must follow these steps:

 1) Install mouse driver for DOS to an appropriate directory of your hard disk. Installation may be carried out from your mouse diskettes by running the setup program from that disk.

 2) Place a line into your AUTOEXEC.BAT (or into CONFIG.SYS) which will start the mouse driver whenever you turn on your computer. This line is typically something like MOUSE.EXE (when you write it into AUTOEXEC.BAT) or DEVICE=C:\MOUSE\MOUSE.SYS (when you write it into CONFIG.SYS). Refer to your mouse documentation for details.

 3) Reboot your computer for changes to take effect.


Graphic screen dump

   If you press <Alt-P>, the contents of the graphic screen will be saved (dumped) to a 16-color Windows Bitmap (BMP) file to help document illustration. This operation does not require any additional software element (such as Microsoft Windows (TM) or a screen-capture program). The output file will get a unique name, so successive screen dump operations do not destroy previously dumped files.

   Images will be created in the directory that TEMP (or TMP) environment variable points to. These variables are normally set in your AUTOEXEC.BAT file. We suggest  a TEMP variable setting  in your AUTOEXEC.BAT if there is none. See directory of temporary files for details.

   Images are in uncompressed bitmap format, so their size is approximately 150 Kbytes. Colours of images are mapped (transformed and lightened) to ease inserting them into printable documents. Colour mapping procedure can be fully customised by the user. You can find information about colour mapping schemes in HYPC.INI file.

See also

   BMP colors section in HYPC.INI


Refits

  Refits (previous alternative fits, repeated fits) are created when the user make repeated fits in a spectrum region.. Each fit becomes  a refit of the actual region.

  If a region has refits, REFIT prompt appears on the info page. You can switch between refits with mouse or from keyboard.

Important! Although Hypermet-PC maintains all refits in the LogBook, only those will be put in the result files (*.pkl, etc.) which were just left on the screen before advancing to the next region. This way  the user is allowed to select a best refit.

See also

  Keyboard commands


The Hypermet-PC screen

  In general, the most part of the screen is occupied by the spectra to be evaluated. In expanded mode , this window is divided into  halves. The main menus and sub-menus are accessible in the upper pull-down menu bar. At the right side, approximately one fifths of the screen area is reserved for an info page containing detailed results such as peak areas, resolution, chi-square data, etc.

Pull-down menu bar

   User can select the menus by mouse or by typing the highlighted characters while holding down the <Alt> key (e.g. Alt-F). Some menus split into input boxes facilitating parameter settings and input/output control. By using the arrows and the Enter key one can also select any menus easily from keyboard.

Channel cursor

   Channel cursor is a vertical bar moving on the top of data points which representing measured counts. In Hypermet-PC, there is only one channel cursor per display window, but because more than one display window may be open at the same time (e.g. the upper window for fitting details and a residual window below), therefore two synchronised channel cursors may appear in the upper and lower expanded windows.

Cursor info bar

   During spectrum analysis a rectangular area is reserved at the bottom of the screen, where the program displays the actual position of the channel cursor in channel number and in energy units, as well as the channel content in counts.

   If optional program modules (ADC test, Efficiency, etc.) are used, additional information is displayed here (e.g. percentage deviation or calibration data).

   Sometimes green buttons also appear here  as fast keys for common operations (such as the LOG green button toggling between linear and logarithmic display mode).

Info page

  In this rectangular area the program outputs detailed procedure-specific data (chi-squares, fitted ranges, etc.) arranged on several pages. Occasionally the 'REFITS' message pop-up here in case if additional fits exist for the same region (in the Eval module). Any page can be viewed by the <Page Up> or <Page Down> buttons.

Info sub-pages

  In the Eval module there may be sub-pages of every region, which show the refits of the active region. These sub-pages can be select by clicking on the arrows on the left and right side of the 'REFITS' text.

See also

   Keyboard

   Mouse

   Expanded mode


Expanded mode

  In this spectrum drawing mode screen is divided into upper and lower expanded windows. In the lower window full spectrum is displayed with the rubber band. Upper half contains only an expanded part of the spectrum. The user can switch expanded mode on/off  with selecting Display / Expand Off/On menu in the main pull-down menu.

See also

   The Hypermet-PC screen


Region bound setting window

   You can specify left and right boundaries in channels for computing differential and integral curves. After you enter new values, Hypermet-PC will automatically recalculate and display the appropriate curve for the specified region.


About box

   This box provides general information  about Hypermet-PC. You can check here the internal version number of Hypermet-PC as well as the amount of free memory available for the program. To close this  window, click on OK or press <Esc>.

See also

   System requirements


System requirements

Hypermet-PC hardware and software requirements are kept at a minimum according to IAEA recommendations.

Computer

  Hypermet-PC requires a fully IBM-compatible PC, at least a 80386 processor and math coprocessor to run. In order  to resolve complicated multiplets within reasonable period of time a fast 80486 or Pentium based machine is recommended.

Memory

  Typically, Hypermet-PC needs less than 2 megabytes of extended memory for safe operation. For starting the program, user must ensure 200 kilobytes of conventional memory and 1 megabyte of extended memory. No EMS memory is required at all.  Appropriate PIF (program information) files for Windows 3.x and Windows95 users with the appropriate memory settings are provided.

Disk space

  The main Hypermet-PC program takes less than 1 megabytes of hard disk space. On-line help file takes about 400 kilobytes, while the Nuclide ID libraries requires further 1.5 megabytes. Full installation needs about 3 megabytes.

Additional hardware

- Hypermet-PC needs a mouse or other compatible pointing device.

- To run evaluation modules, user must have an appropriate hardware key plugged into the parallel port of the machine before starting Hypermet-PC.

Operating system

  Hypermet-PC was tested and proved to be operational in DOS 6.2x, Windows 3.x, Windows 95 and Windows NT environment.

Additional software

- Because Hypermet-PC is a DOS-extender based protected mode application, it is necessary to install a memory manager application, such as HIMEM.SYS from Microsoft Corp. before use. See operating system documentation for details. During the configuration procedure remember, that Hypermet-PC does not require EMS memory at all.

- Mouse driver or other device driver for compatible pointing device. See your documentation provided by the mouse manufacturer for details.

- Users with DOS or Windows 3.x systems should install a disk cache utility, such as SMARTDRIVE from Microsoft Corp. to speed up the disk operations during evaluation.

- Users with Windows NT _must_ install a system driver for the hardware key before running Hypermet-PC. This driver is located on the second installation disk under NT_KEY directory.

Notes

- During the operation of Hypermet-PC fitting algorithm, several temporary files are created in the temporary directory of your computer. These files may take megabytes during the program run, but normally they are deleted upon program exit.

- When spectrum evaluation ( quality assurance tests) are performed, log files will be created which hold evaluation results. These files - stored in that directory which one the user specifies - take a considerable amount disk space. The log files will not be deleted automatically upon program exit.

See also

   Installing mouse on your computer

   Logbook concept of Hypermet-PC


Nuclide ID Libraries

   Nuclide ID module contains two independent nuclear library: one for NAA and one for PGAA analytical purposes (for instrumental and prompt gamma neutron activation analysis).

   NAA Library is converted from the Table of Radioactive Isotopes and contains about 2700 gamma lines of about 180 isotopes. Half-lives of isotopes are obtained from the Nuclear Wallet Cards.

  PGAA Library is converted from Prompt-gamma library developed from database created by M. A. Lone et al. Abundance data is obtained from the Nuclear Wallet Cards. Cross section data is obtained from database of S.F. Mughabgab et al.


Prompt-Gamma Library by M.A. Lone et al.
[LONE]

Prompt Gamma Rays from Thermal-Neutron Capture, M. A. Lone, R. A.

Leavitt, D. A. Harrison, Atomic Data and Nuclear Data Tables 26, 511 (1981)


Table of Radioactive Isotopes
[TORI86]

Table of Radioactive Isotopes by E. Browne and R. B. Firestone, John

Wiley & Sons, Inc. (1986)


Nuclear Wallet Cards
[WALLC95]

Nuclear Wallet Cards, J.K. Tuli. (5th Edition,1995)


Neutron Cross Sections data by S. F. Mughabghab et al.
[MUGAB81]

Neutron Cross Sections, Vol.1, Part A: Z=1-60 (1981)

S.F. Mughabghab, M. Divadeenam, and N.E. Holden.

Vol.1, Part B: Z=61-100 (1984)

S.F. Mughabghab, Academic Press, Inc.


References

We provide a comprehensive listing below about the cited references involved in the on-line Help file.

  [FDEC89]  - decay schemes for nuclides

  [GENIE1] - Genie-PC manual

  [LONE] - Prompt-gamma data

  [MUGAB81] - Neutron cross section data

  [PHILMARL] - description of the original HYPERMET program

  [SAMPO1] - SAMPO article

  [SAMPO2] - SAMPO article

  [TORI86] - Table of Radioactive Isotopes

  [WALC95] - Nuclear Wallet Cards


Phillips and Marlow article
[PHILMARL]

G. W. Phillips,  K. W. Marlow:

Program HYPERMET for automatic analysis of gamma-ray spectra from germanium detectors;

Nucl. Instr. Methods 137 (1976) 525.

See also

   NRL Memorandum Report 3198; Naval Research Laboratory, Washington D. C. (January 1976)


De Corte and Simonits article
[FDEC89]

F. DE CORTE, A. SIMONITS:

k0 - measurements and related nuclear data compilation for (n, gamma) reactor neutron activation analysis;

Journal of Radioanalytical and Nuclear Chemistry, Articles, Vol.133, No. 1 (1989) 3-41 and 43-130


Genie-PC User's Manual
[GENIE1]

Canberra Industries:

GENIE-PC Ver. 2.0

User's Manual (1994)


Sampo article #1
[SAMPO1]

J. T. Routti and S. G. Prussin:

Nucl. Instr. Methods 72 (1969) 125 pp.


Sampo article #2
[SAMPO2]

P.A. Aarnio, M. T. Nikkinen and J. T. Routti:

SAMPO-90 high resolution interactive gamma-spectrum analysis including automation with macros;

J. Radioanal. Nucl. Chem. Articles 160, (1992) 289-296.


Other references (not cited yet)

B. Fazekas, H. Rausch,  A. Simonits, L. Dabolczi and G. Molnár: PC-based gamma spectroscopy software for k0-NAA  Proc. Int. k0 Users Workshop, Gent, Sep 30 - Oct 2, 1992, De Corte F. ed. (U. Gent) pp. 29-32

KAYZERO - Element concentration Calculation using the k0-Standardization Method, Version 3.01 Users Manual (1994) DSM Research, Geleen (NL)


Nuclide ID library info window

   You can get general information of presently loaded nuclide library.

   At present only two libraries are provided for analytical purposes: one for NAA (Neutron Activation Analysis) and one for PGAA (Prompt Gamma Activation Analysis). If you specify the analytical method, an appropriate nuclide library will automatically be loaded.

See also

   Nuclide ID module


Logbook concept of Hypermet-PC

   The Logbook concept helps skilled analysts solving sophisticated fitting problems and improves the reliability of automatic analysis  Logbook is an internal database to store all important data involved in a specific evaluation.

   Internal databases are used in Eval, Nonlinearity, Efficiency and FWHM modules. While in Quality Assurance program modules all modifications are automatically stored in the internal database and displayed without delay on the screen, fitting results stored in Eval module are displayed only when selecting Logbook / Region menu. To switch off displaying the fitting results, user should simply click in the lower expanded window.

   To retain the particular status of an evaluation, logbooks can be saved in a disk file. These files are called log files and the evaluation state can be restored by reloading them into the appropriate program module. The relevant Log files of different program modules: evaluation log file (*.LOG), nonlinearity log file (*.LIN), efficiency log file (*.EFF), resolution log file (*.FWH).

Logbook in Eval module

   After an automatic spectrum fit in Eval module, all  fitting details are stored in a database and user can browse for details in Logbook / Region menu.

   User is prompted to check only those faulty fits marked with an asterisk in the fitted regions list.. The bad fits can usually be improved by manual interactions and the repeated fits (called refits in the Hypermet-PC terminology) are also stored  in the logbook, therefore, user can select the best fit for a specific region of the spectrum. In the final text format of the report file only the data of the selected regions will be placed.

   By selecting the Logbook / Peak menu, user can revise the list of fitted peak centroids.  Note that if fitted regions overlap or in the case of refits, peaks whose centroid is equal within 3 sigma boundaries are treated identical

See also

   Region manipulation window

   Peak manipulation window


Region manipulation window

   After an automatic fit you can revise fitted regions using this pop-up window. A scrollable list displays the boundaries of the fitted regions. At the end of the rows an asterisk (*) may appear indicating  that the Chi-square/(1+N*Sigma limit  is greater than 1.0. In these regions  manual refit with modified parameters is justified..

   Region boundaries may be changed by selecting appropriate radiobuttons at the bottom of the list.

   A specific region may be selected by double-click on that region or by a simple click and by pressing the View button.

   If necessary, user may delete the whole region by selecting a region with simple click and by pressing the Delete button.

Notes:

- Deleting a region is necessary only when the fit is defective  due to numerical reasons or improperly set fitting parameters (e.g. using by accident the Variable Peak Option for the whole spectrum).

- It is possible to delete an individual peak from a given region by selecting Logbook / Peak menu and using the peak manipulation window. This operation may be necessary if user refits the region and wants to eliminate an faulty peak inserted automatically.

See also

   Region manipulation window

   Peak manipulation window

   Logbook concept of Hypermet-PC

   Using pop-up windows


Peak manipulation window

   After an automatic fit user can scrutinise fitted peaks using this pop-up window. Available control elements:

Scrollable list

  This list displays the centroids of the fitted peaks in keV or in channel unit. See also details.

Unit radiobuttons

  To change the unit of peak centroids displayed, select the appropriate radiobutton. The unit setting also controls  the loading of the peak list (see Load list press button).

View button

  To display a specific peak (with the surrounding peaks in the region), double-click on the peak centroid value or select it with a simple click and press this button.

Delete button

  Press this button to delete the peak from the region after you selected the peak with a simple click on the list.

Insert  button

Insert an unevaluated peak into the region at the position where the channel cursor stands.

Load list  button

Insert a set of unevaluated peak positions or peak energies from a disk file to the logbook.

See also

   Region manipulation window

   Peak manipulation window

   Logbook concept of Hypermet-PC

   Using pop-up windows


Peak list

(Peak manipulation window)

   At the end of each row an asterisk (*) or a letter u may appear. The asterisk means a non-significant peak (where the standard deviation of the area is larger than the area itself), while the unevaluated peaks are marked by letter u.

   Unevaluated peaks come into being by loading a peak position / peak energy file using the Load list press button. These peaks are stored in the logbook only but has no fitted equivalent in the actual region.

See also

   Peak manipulation window


Delete button

(Peak manipulation window)

   Delete operation should be accomplished if  a false peak is inserted into a region and user is about to make a refit  after changing the fitting conditions (e.g.  a wider background has been set).

   User must delete the previously fitted false peaks manually, because the fitting algorithm fixes the position of all peaks in consecutive fitting trials. This means that if a peak has been found in a given region, the algorithm will not remove it even if the initial fitting parameters have been changed.

See also

   Peak manipulation window


Insert button

(Peak manipulation window)

   Inserting a peak into a region means a suggestion to insert an unevaluated peak at the position of the channel cursor. Afterwards user should refit the actual region by selecting Fit menu in order to change the unevaluated peak status to normal (evaluated).

   If the  fitting procedure finds a significant peak in the region at the suggested location, then a new peak will be fitted to that region. If the new peak is not significant, then the region remains unchanged (that is, Hypermet-PC abandons the newly inserted peak).

See also

   Peak manipulation window

   Peak inserting window


Load list button

(Peak manipulation window)

   When  the Load list button is pressed, Hypermet-PC inserts from a disk file a set of unevaluated peak positions or peak energies to the logbook. The type of the data retrieved from the file depends on the status of the unit radiobutton: if the unit is set to channel, then peak positions in channel) are loaded from the input file. If the unit is set to keV, then the centroid energy of peaks are inserted into the logbook.

   The newly inserted peaks are treated as unevaluated peaks, so user should perform an (automatic) evaluation after a peak list loading.

   With the peak list loading feature the user may perform a convenient mass evaluation by suggesting peak positions for the fitting algorithm.

Notes

- It is possible to load the peak positions using different output file formats: Short, Peaklist, Sampo PTF or ASC..

- Apply this feature with caution. Practice shows that even consecutive measurements achieved with a very stable measuring setup may result a shift in peak positions (e.g. due to changes in the amplification), therefore the positions of the peaks expressed in channels may shift from one measurement to another. However, a good energy calibration may reduce the  effect  of system instabilities.

See also

   Peak manipulation window


Peak inserting window

   You can specify the position and the position uncertainty of a newly inserted peak here.  The default values are obtained by using the position of the channel cursor.

Note:

   When user inserts a peak into a region, that means you only  suggest a possible peak for the fitting algorithm. After insertion, user should refit the actual region by selecting Fit menu. Hypermet-PC fitting algorithm might insert a new peak to the region if it is significant.., If not, then the region remains unchanged even if the suggested peak position was fixed. .

See also

   Region manipulation window

   Peak manipulation window

   Logbook concept of Hypermet-PC

   Using pop-up windows


Quit Eval confirmation window

   You can leave Eval module with clicking  OK., If the  fitting results are acceptable, select 'keep' in 'Log file' section. Hypermet-PC will store them in a Log file, from which you can retrieve them  later.

   If you are dissatisfied with present results, select 'delete' in 'Log file' section and results will not be stored in log file.

See also

   Using pop-up windows


Peak tip window

   To facilitate an easy  energy calibration, Hypermet-PC provides a dedicated data library of nuclides (152-Eu, 182-Ta etc.) used for calibration purposes.

   When a single spectrum peak is selected for calibration and help is requested by pressing Tip gamma lines with energies  in the vicinity of that of the selected peak will be listed in a pop-up window.. If user select one by double-clicking, then the literary energy and  uncertainty values of that line will be read into the input box, overwriting its previous content. Using this feature,) a precise calibration can be quickly carried out even without remembering exact data values .

Note:

   Please note that this procedure will not search for a matching line  in Nuclide ID Library, but ONLY  in the editable 'Nuclid.std' file. Therefore, if you are dissatisfied with the tips, quit Hypermet-PC and insert appropriate gamma lines into your 'Nuclid.std' file. Next time when you start Hypermet-PC, changes take effect.

See also

   Nuclid.std file

   Using pop-up windows


Spectrum evaluation calibration window
Calibration window

   You can set the two-point energy and FWHM calibration parameters, as well as the mode of energy calibration in this pop-up window.

FWHM calibration input boxes:

  At the top of the data input boxes type in two pairs of peak position and peak FWHM data. The FWHM values   should be specified in channels.

Energy calibration input boxes:

  At middle of the pop-up window four data input boxes are  for each of the two energy calibration points: the position of the peak (with uncertainty of the position) and the energy value of a literary peak (with uncertainty in the literary value).

Energy option radiobuttons:

  At the bottom of the window the energy calibration method may be specified by  Energy option radiobutton.

Radiobuttons between input boxes

  If the Logbook is open, the actual position of the channel cursor will be copied to the attached input boxes pressing these buttons. This way  the tedious manual typing can be eliminated.

Tip buttons

   Pressing Tip buttons a Peak tip pop-up window appears with literary energies which are the nearest gamma lines around the energy value specified in the energy box. User then may select a line by clicking with the mouse. (The gamma lines offered are taken from Nuclid.std file.)

See also

   Spectrum evaluation with Hypermet-PC

   rough fwhm calibration

   Using pop-up windows


Radiobuttons

(Calibration window)

   If the Logbook is open (previously fitted results are displayed on the screen by selecting Logbook / Region menu), then four radiobuttons appear between data input boxes. Each radiobutton belongs to a calibration parameter (two for FWHM  and two for energy calibration.

   If user clicks on a radiobutton, Hypermet-PC will automatically insert the position of the channel cursor to the attached input box. If the selected radiobutton was attached to the FWHM calibration input box, then the peak width  will be automatically entered.

   This way you can simply enter the position and FWHM of the selected peak  for calibration purposes. Note that the values to be entered depend on the selected energy calibration method. If energy calibration method is set to Fix position, then the values remains unchanged during program execution. If Fitted position is selected, then program automatically replaces the channel values with the nearest fitted peaks position (within 2*sigma distance).


Eval parameters setting window

   This window is intended for Hypermet-experts only to  control   the peak fitting algorithm. The default values appearing in the input boxes are used in the original FORTRAN code.

Note:

   In general we do not recommend to change these values from this window. Non-experts ucan change some of these parameters in an appropriate pop-up windows available from Settings / Fine tune menu. Inappropriate settings may cause abnormal operation of peak fitting algorithm.

See also

   Using pop-up windows


Fitting start window

(Eval module)

  You can initiate fitting of one or more regions (spectrum areas) from this window.

- Left ch and Right ch input boxes contains the region bounds for fitting. See details.

- Width is the estimated FWHM of peaks to be fitted in the actual region. The value appeared in the input box is computed from the two-point peak FWHM calibration curve, but can be overwritten to fit the region with a different peak width setting. See details.

- Try box contains the number of peak insertion tries during the peak fitting. See details.

- Auto check box controls the behaviour of the fitting algorithm after a region fit. If this box is checked, then algorithm automatically fits all the regions until the spectrum end. See details.

- FIX check box controls the background determination method. If it is checked, then the background will be fixed to the values displayed in Left ch and Right ch input boxes. Otherwise peak fitting algorithm automatically finds the optimal background boundaries for the actual region.

- If ROI check box is set (checked), then the automatic region evaluation will be performed only on ROIs. If it is cleared, then normal evaluation is made on consecutive regions.

- Peak integration check box is enabled, when user looks at the logbook and a region of channels is selected by the right mouse button. By pressing the OK button a very simple peak integration will be performed on the selected channels. See details.

See also

   Using pop-up windows


Left and Right ch input boxes

(Fitting start window, Eval module)

   Left ch and Right ch input boxes contains the region bounds for fitting (in channels). These values are set by the following rules:

  - If user looks at the Logbook (displays fitting results by selecting the Logbook / Region menu), and selected channel counts by sweeping over the channels holding down the right mouse button, then the boundaries of the selected counts (which are displayed in blue) will be written into the input boxes.

  - If user looks at the Logbook, but fixed region is not selected (there are no counts displayed in blue on the upper expanded window) then the boundaries of the displayed fit will be written into the input boxes.

  - If user does not look at the Logbook, then the boundaries of the spectrum part displayed in the upper expanded window will be used.

See also

   Fitting start window


Peak width input box

(Fitting start window, Eval module)

   Width input box contains the estimated FWHM of peaks to be fitted in the actual region. The appeared value  is computed from the two-point peak FWHM calibration curve. In general, when user has a rough FWHM calibration, this value should not be changed. However, this input box  is indispensable for the rough peak width calibration procedure.

   Please note that Hypermet-PC needs at least a rough peak width estimation for a reasonable fitting. In addition, an approximate two-point energy calibration is recommended

See also

   Fitting start window


Try check box

(Fitting start window, Eval module)

   When the fit is unsuccessful, then Hypermet-PC automatically attempts to correct the error by searching new peaks in the residual.

   The value in the TRY check box is the maximum number of tries allowed

See also

   Fine tune/Sigma menu

   Peak fitting algorithm


Spectrum library content listing window

   This pop-up window appears when user opens a spectrum library  in Main module. The scrollable list contains all the spectra stored in the library file. User can  select and then load a spectrum  by pressing OK . Pressing the Cancel button or the Esc key will abandon the spectrum loading process.

See also

   Information about Nuclide ID libraries

   Using pop-up windows


Efficiency calibration polynomial settings window
Polynomial settings window

(Efficiency Module)

Degree: gives the order of polynomial applied to fit the input data points. Typically, a second to eighth order polynomial ensures suitable approximation for a Ge detector efficiency curve.

Notes:

- If the program could find but only a few gamma lines of a multi-line gamma source, this probably indicates a poor energy calibration and / or missing nonlinearity calibration. For example, with a badly calibrated system, typically 100-1000 sigma value may be necessary for the accurate peak identification! First of all, user should create a nonlinearity calibration with Nonlin module, then load the nonlinearity calibration curve into Eval module and re-generate the peaklist file and after these procedures may return back to efficiency module. If peaks are still not identified, try to slightly increase the value of identification threshold.

- After you changed the threshold value, changes take effect only if you remove the whole dataset by using of Dataset / Remove menu and by reloading it by Dataset / Load.

See also

   Nonlin module pull-down menu

   Using pop-up windows


Calibration source selecting window

   After user selects Dataset / Load Abs. In Efficiency module, a pop-up window offers all available activity-calibrated radioactive sources if their nuclear and certificate data have been entered in Nuclid.std file. Select a source with the left mouse button and pressing OK, then the absolute activity and its error is computed for the source. Efficiency module algorithm then searches for the gamma lines of isotope(s) present in the source.

  If the required number of gamma lines are identified, the data points will be immediately displayed on the screen. In case of applying more than one absolute sources,  data points from that sources must fit on the efficiency curve without any normalisation. If considerable deviation is found between the data points of absolute calibrated sources, then user must check activity calibration data in Nuclid.std file.

See also

   Nuclid.std file

   Using pop-up windows


Computation error report window

   This pop-up window appears when a serious computational error occurs during any floating point operation. These errors are typically displayed after an erroneous fit (especially when initiating an automatic fit when  the Variable Peak Width Option is switched on).

   A scrollable list is shown with a maximum of 100 error messages. These messages are useless in  most cases, but may inform  the user about the quality the produced result (for example, a fit is not acceptable or not).

   It is possible to save or directly print these messages by selecting the Save or Print press buttons, respectively.

See also

   Using pop-up windows


Intersection setting window

  This pop-up window serves to set intersection points of the baseline and the fitted curve, therefore determines the linear transformation of data points. These intersections define the zero deviation - that is, the channels where the system was calibrated

See also

   Using pop-up windows


Thresholds window

(FWHM module)

  This pop-up window contains three data input boxes. Changing these parameters may affect the result of the FWHM curve fitting process.

Identification [sigma]: FWHM module will search for matching measured and literary peaks in the loaded datasets and in the Nuclid.std file and then displays the peak width versus energy information for the matched peaks. Peaks are treated as matched and will be involved in the fit if a measured peak is within the vicinity of a measured peak plus and minus overall uncertainty value multiplied by this value. One sigma value is the overall quadratic uncertainty of the actually measured and library peak positions.

Acceptance of CHSQ: On the info page chi-square values for each isotope will be marked with green or red colour. The colour depends on the value set here: if chi-square for an isotope is less than this threshold value, then it will be in green , otherwise it will turn to red.

Notes:

- If the program could find only a few gamma lines of a multi-line gamma source, try to increase the value of identification threshold (a typical change is 10 or more). After you changed the threshold value, changes take effect only if you remove the whole dataset by using of Dataset / Remove menu and by loading it back by Dataset / Load Sets or Load Each.

- The data of isotopes is obtained from the Nuclid.std file, which is a user-editable text file, thus it can be extended with further data for particular purposes.

See also

   Nuclid.std file

   Using pop-up windows


Nuclide selection window

(Quality Assurance modules)

  This pop-up window is generally used to select one or more nuclides included in the Nuclid.std file. If you intend to select only one nuclide from the list, scroll the list until the nuclide is displayed and click on it, then press OK .

  If you want to select more nuclide at the same time, click on a nuclide and hold down the <Ctrl> key on the keyboard while clicking on other nuclides.

  If your favourite nuclide is not shown on the list, quit Hypermet-PC, edit Nuclid.std file and restart the program.

See also

   Using pop-up windows


Nuclide range customizing window (Nuclide ID module)
Nuclide range customising window

(Nuclide ID module)

  This pop-up window lets the user to customise the set of nuclides (or elements)  involved in the analytical process.

Two panel is used for collecting the nuclides to be involved or  excluded  from the analysis.

  To move nuclides from the left panel, (involved nuclides) to the right panel (excluded nuclides), select the nuclide on the left side and press the arrow pointing from left to right. To reinsert a specific nuclide into the analysed nuclide range, select one or more nuclides on the right side and press the arrow pointing from right to left. (To select more than one nuclide at the same time, hold down the <Ctrl> key on the keyboard while clicking on a nuclide with the left mouse button.)

   When you are ready with the selection, press OK to initiate the reduction or extension of the nuclide range. If you have changed your mind, press Cancel.

Notes

  In the left and right panel all nuclides present in the appropriate nuclide library are listed.. If  the NAA analytical method is selected, then only  nuclides and reactions characteristics in this method are considered.. For the PGAA method, only chemical elements are listed (isotopic data weighted with the isotopic abundance).

See also

   Binary Hypermet-PC Library

   Using pop-up windows


NAA measurement parameters setting window

   User can enter measurement parameters for NAA in this pop-up window. At present, only the  cooling time and a sample code (a simple text line) can be set.

 - Setting the actual cooling time is essential for proper half-life filtering.

 - Sample code will appear in Nuclide ID Report file (*.NUR).

See also

  Half-life filtering

  Nuclide ID algorithm

  Nuclide ID Report file

   Using pop-up windows


Nuclide ID parameters window

Nuclide ID parameters control the behaviour of the identification algorithm.

Energy range to analyse: these values are used as boundaries to restrict  the library  (that is peak energies must  fall between these limits). User should change these values only for specific purposes.

Additive peak position uncertainty: these values serve as parameters of a linear function which increases the uncertainty in the peak positions during peak identification. See further details.

Random sum peak test values controls the detection of random sum peaks (that is, the twice the energy of high intensity peaks /parent peaks/ ). If both  limits below are exceeded, then program will indicate the doubled energy peak as random sum peak in the final Nuclide ID report.

- minimum parent rate: minimum rate of the parent peak in counts per second (cps) unit to consider the resulting doubled energy peak as random sum peak.

- minimum parent area: minimal area of the parent peak in counts to consider a doubled energy peak as a random sum peak.

Half-life exclusion: this factor is a multiplier, which is used to filter out nuclides by the actual cooling time and half-life multiplied by this value. See further details.

Peak matching limit: if Nuclide ID algorithm  matches two peaks with lower P value than this threshold value, then the peak match is not stored in internal database (treated as false match).

See also

   Q list of nuclides

   Using pop-up windows


Nuclide ID report content customizing window
Nuclide ID report content customising window

   In this window you can customise  the Nuclide ID report format.

Sections appearing in Nuclide ID report:

- Q list of nuclides

- Half-life filtering

- Nuclides found

- Unidentified peaks

- Escape peaks

- Nuclides by peaks

Q list cut-off value: if a nuclide has greater Q-value than specified here, it will appear in the Q-list of Nuclide ID report, otherwise it is not shown. This value is used to customise this list and doesnt affect other report sections.

Note

  If you change your report format, you are not  compelled to make a new analysis, only to create a new report. In contrast, when changing any other parameters in Nuclide ID setting menu, you must start a new analysis to effectuate a new setting.

See also

  Q list of nuclides

  Nuclide ID algorithm

  Description of Q and P values

  Using pop-up windows


File saving windows

   File saving windows serve as a convenient interface for saving  report files. General input elements displayed on these windows are the following:

File name input box: upper left box on the window. The output file name may be typed into this box. Some file saving window contains a New button, which overwrites the window content with a new file name if pressed.

File list panel: the left panel on the window. It contains  files  found in the actual directory and have the same file extension.

Directory list panel: the right panel on the window. It contains the sub-directories which were found in the actual directory, as well as the directories above it.

New button (optional): on some file saving windows you can find this button.. When pressed , a new file name will be written into the file name input box, overwriting its previous content. This way the program provides a default file name for the output file and user will be freed from typing a file name.

OK button: accept the typed file name and closes the window.

Cancel button: discards changes and closes the window.

Note:

  Since Hypermet-PC is a DOS-based program, the long file names of Windows95 will be mapped (transformed) in the left file list panel, as well as long directory names into the right directory list panel.

See also

   File loading windows

   Using pop-up windows


File loading windows

   File loading windows serve as convenient interface for loading different types of files. General input elements displayed on these windows are the following:

File name input box: upper left box on the window, where the name of the input file may be typed.

File type roll-down list (optional): this upper right list contains different file types for that procedures, which allow to load input files with different formats. For example, in Quality Assurance modules, peaklists may be loaded in different output file formats..

File list panel: the left panel on the window. It contains the files which were found in the actual directory and have the searched file extension.

Directory list panel: the right panel on the window. It contains the sub-directories which were found in the actual directory, as well as the directories above it.

OK button: accept the typed file name and closes the window.

Cancel button: discards changes and closes the window.

Note:

  Since Hypermet-PC is a DOS-based program, the long file names of Windows95 will be mapped (transformed) in the left file list panel, as well as long directory names in the right directory list panel.

See also

   File saving windows

   Using pop-up windows


Quality Assurance report window

   Using this pop-up window, user may save the results of a nonlinearity, efficiency or FWHM fit in short or CSV report format. To save a Quality Assurance report:

 1) Set directory. Change to the appropriate destination directory (where output report file should be stored) by clicking on directory names listed in the right panel.

 2) Specify file name. Type a report file name into the upper left input box, or press New button. In the latter case the name of the actual Quality Assurance log file will be written into the input box with file extension SHO or CSV.

 3) Press OK button to save the report file, or press Cancel to abandon saving.

Note

  If user selects a previously saved report file for output, the new results will be appended to the end of the report file. Thus the old evaluations will not be deleted, but the size of the file will grow. To revise newest results, user must search for the latest saved report data section at the end of the output file.

See also

   File saving windows

   Using pop-up windows


Efficiency log file loading window

   Using this pop-up window, user may load a previously saved efficiency log file (*.EFF). To load an efficiency log file:

 1) Set directory. Change to the appropriate destination directory (where saved EFF file is stored) by clicking on directory names listed in the right panel. All the efficiency files may be found in the actual directory and  listed in the left panel.

 2) Select file. Click on the appropriate efficiency file in the left panel.

 3) Press OK button to load the log file, or press Cancel to abandon loading the efficiency file.

See also

   File loading windows

   Using pop-up windows


Efficiency log file saving window

   Using this pop-up window, user may save a previously created efficiency log file (*.EFF) to another directory with a different name. To save an efficiency log file:

 1) Set directory. Change to the appropriate destination directory (where saved EFF file should be stored) by clicking on directory names listed in the right panel. All previously saved efficiency files may be found in the actual directory and  listed in the left panel.

 2) Specify file name. If you would like to give a new name for your efficiency log file, type it in the file name box (upper left). If you want overwrite content of a previously saved EFF file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK button to initiate the saving of the log file, or press Cancel to abandon saving the file. If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   File saving windows

   Using pop-up windows


New efficiency log file specifying window

   Using this pop-up window, user may specify the name and directory for a newly created efficiency log file (*.EFF). To supply the name of a new efficiency log file:

 1) Set directory. Change to the appropriate destination directory (where saved EFF file should be stored) by clicking on directory names listed in the right panel. All previously saved efficiency files may be found in the actual directory and  listed in the left panel.

 2) Specify file name. If you would like to give a new name for your efficiency log file, type it in the file name box (upper left). If you want overwrite content of a previously saved EFF file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK button to end the file name specification, or press Cancel to abandon the operation. If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   File saving windows

   Using pop-up windows


Nonlinearity log file loading window

   Using this pop-up window, user may load a previously saved nonlinearity log file (*.LIN). To load a nonlinearity log file:

 1) Set directory. Change to the appropriate destination directory (where LIN file will be stored) by clicking on directory names listed in the right panel. All the nonlinearity files found in the actual directory will be listed in the left panel.

 2) Select file. Click on the appropriate nonlinearity file in the left panel.

 3) Press OK button to load the log file, or press Cancel to abandon loading the nonlinearity file.

See also

   File loading windows

   Using pop-up windows


Nonlinearity log file saving window

   Using this pop-up window, user may save a previously created nonlinearity log file (*.LIN) to another directory with a different name. To save a nonlinearity log file:

 1) Set directory. Change to the appropriate destination directory (where LIN file will be stored) by clicking on directory names listed in the right panel. All previously saved nonlinearity files found in the actual directory will be listed in the left panel.

 2) Specify file name. If you would like to give a new name for your nonlinearity log file, type it in the file name box (upper left). If you want overwrite content of a previously saved LIN file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK  to initiate  log file saving, or press Cancel to abandon saving the file. If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   File saving windows

   Using pop-up windows


New nonlinearity log file specifying window

   Using this pop-up window, user may specify the name and directory for a newly created nonlinearity log file (*.LIN). To supply the name of a new nonlinearity log file:

 1) Set directory. Change to the appropriate destination directory (where saved LIN file will be stored) by clicking on directory names listed in the right panel. All previously saved nonlinearity files  found in the actual directory will be listed in the left panel.

 2) Specify file name. If you would like to give a new name for your nonlinearity log file, type it in the file name box (upper left). If you want overwrite content of a previously saved LIN file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK  to end the file name specification, or press Cancel to abandon the operation. If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   File saving windows

   Using pop-up windows


 FWHM log file loading window

   Using this pop-up window, user may load a previously saved FWHM log file (*.FWH). To load an FWHM log file:

 1) Set directory. Change to the appropriate destination directory (where saved *.FWH file is  stored) by clicking on directory names listed in the right panel. All FWHM files found in the actual directory will be listed in the left panel.

 2) Select file. Click on the appropriate FWHM file in the left panel.

 3) Press OK  to load the log file, or press Cancel to abandon loading the FWHM file.

See also

   File loading windows

   Using pop-up windows


FWHM log file saving window

   Using this pop-up window, user may save a previously created FWHM log file (*.FWH) to another directory with a different name. To save an FWHM log file:

 1) Set directory. Change to the appropriate destination directory (where saved *.FWH file will be stored) by clicking on directory names listed in the right panel. All previously saved FWHM files  found in the actual directory will be listed in the left panel.

 2) Specify file name. If you would like to give a new name for your FWHM log file, type it in the file name box (upper left). If you want overwrite content of a previously saved *.FWH file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK  to initiate the saving of the log file, or press Cancel to abandon file saving . If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   File saving windows

   Using pop-up windows


New FWHM log file specifying window

   Using this pop-up window, user may specify the name and directory for a newly created FWHM log file (*.FWH). To supply the name for a new FWHM log file:

 1) Set directory. Change to the appropriate destination directory (where saved *.FWH file will be stored) by clicking on directory names listed in the right panel. All previously saved FWHM files  found in the actual directory will be listed in the left panel.

 2) Specify file name. If you would like to give a new name for your FWHM log file, type it in the file name box (upper left). If you want overwrite content of a previously saved *.FWH file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK  to end the file name specification, or press Cancel to abandon the operation. If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   File saving windows

   Using pop-up windows


Peaklist loading window

   This pop-up window is used in several program modules of Hypermet-PC, and helps to load previously saved peaklist report files in various formats. To load a specific peaklist report file:

1) Set directory. Change to the appropriate destination directory (where saved *.FWH file is stored) by clicking on directory names listed in the right panel. All report files in the actual directory will be listed in the left panel, if their file type (and file extension) is identical with the content of the roll-down list box (upper right in the window).

 2) Specify file type. If file type is not appropriate, press and release the push button of the list (with up-down arrow). The file type list box rolls down and the type of the peaklist report file may be selected.

 3) Select file. Now the content of the left panel is refreshed, and only the specified file types are shown i. Click on the appropriate peaklist file in the left panel.

 4) Press OK  to load the peaklist  file or press Cancel if you have changed your mind.

Available peaklist report formats for loading:

  - PKL Hypermet-PC peaklist

  - SHO Hypermet-PC short file

  - PTF Sampo90 peaktable file

  - ASC User-supplied peaklist

Notes

- The ASC type files (user-supplied peaklists) are allowed only in Eval module for loading unevaluated peak positions into the logbook.

- In the Nuclide ID module only the PKL and SHO file types are supported.

See also

   Using pop-up windows


Peaklist saving window

   Using this pop-up window, user may save a peaklist report file, which contains the results of the fit. To save a peaklist report file:

 1) Set directory. Change to the appropriate destination directory (where peaklist file will be stored) by clicking on directory names listed in the right panel. All previously saved peaklist files found in the actual directory with the same type will be listed in the left panel.

 2) Specify file name. If you would like to give a new name for your peaklist file, type it in the file name box (upper left). To ease this task, Hypermet-PC provides a New button. Pressing this button a new file name will be written into the file name input box, overwriting its previous content. This way the program provides a default file name for the output file (which is identical with the name of the evaluated spectrum) and user will be freed from typing a file name. Or, if you want overwrite content of a previously saved peaklist file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK  to initiate the saving of the peaklist report file, or press Cancel to abandon saving the file. If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   Using pop-up windows


PeaKfitting log file specifying window
Evaluation log file specifying window

   Using this pop-up window, user may specify the evaluation log file (*.LOG), which  contains all details about a spectrum fit. To specify a log file:

 1) Set directory. Change to the appropriate destination directory (where log file will be stored) by clicking on directory names listed in the right panel. All previously saved log files of the actual directory will be listed in the left panel.

 2) Specify file name. Type the name for your log file in the file name box (upper left). To ease this task, Hypermet-PC provides a New button. Pressing this button a new file name will be written into the file name input box, overwriting its previous content. This way the program provides a default file name for the log file (which is identical with the name of the spectrum to be evaluated) and user will be freed from typing the file name. Or, if you want to overwrite the content of a previously saved peaklist file, click on the appropriate file in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK  to initiate the evaluation, or press Cancel to stay in Main module. If you are about to overwrite an old file, but the New button is not pressed, Hypermet-PC will prompt you for confirmation. If New button is pressed, a new file will always be created without confirmation, overwriting the previous evaluation log file.

See also

   Using pop-up windows


Setting file specifying window

   Using this pop-up window, user may save an ASCII format setting file (*.SET), which contains calibration information actually set in Eval module. To save a setting file:

 1) Set directory. Change to the appropriate destination directory (where setting file will be stored) by clicking on directory names listed in the right panel. All previously saved setting files found in the actual directory will be listed in the left panel.

 2) Specify file name. If you would like to give a new name for the setting file, type it in the file name box (upper left). To ease this task, a New button is provided. Pressing this button a new file name will be written into the file name input box. This way the program provides a default file name for the setting file (which is identical with the name of the evaluated spectrum plus .SET extension) and user will be freed from typing a file name. Or, if you want to overwrite the content of a previously saved setting file, click on the appropriate file name in the left panel. In this case the name of the old file will be written into the file name box.

 3) Press OK  to initiate the saving of the setting report file, or press Cancel to abandon saving the file. If you are about to overwrite an old file, Hypermet-PC will prompt you for confirmation.

See also

   Using pop-up windows


Message window

   In this small window Hypermet-PC displays questions, warnings or error messages. Several press buttons may appear on this window serving various purposes (Yes, No, Cancel, etc.)

   Press the appropriate button to answer a question or an exclamation.

See also

   Using pop-up windows


Spectrum loading window

   This pop-up window is used in the Main module to load spectrum files in various formats. To load a specific spectrum file:

1) Set directory. Change to the appropriate destination directory (where spectrum files are stored) by clicking on directory names listed in the right panel. All spectra in the actual directory will be listed in the left panel, if their file type (and file extension) is identical with the content of the roll-down list box (upper right in the window).

 2) Specify file type. If file type is not appropriate, press and release the push button of the list (with an up-down pointing arrow). The file type list box rolls down and the type of the spectrum file may be specified by clicking on it.

 3) Select file. Now the content of the left panel will be refreshed, and only the specified file types will be shown.. Click on the appropriate spectrum file in the left panel.

 4) Press OK button to load the spectrum file or press Cancel if you have changed your mind.

Available spectrum file types:

 S100      *.mca - CANBERRA S-100 MCA's

 AccuSpec  *.dat - AccuSpec MCA's

 ORTEC     *.chn - ORTEC MCA card

 SAMPO-90  *.spe - created by SAMPO-90

 Genie-PC  *.cnf - created by Genie-PC

 ASCII     *.asc - ASCII spectra

 DCHYP     *.spl- compressed format

 Nucleus   *.spm - Nucleus spectrum

 Silena    *.dat - Silena spectrum

Note:

   User may re-define the default spectrum type which is offered by the file loading window by editing the content of the HYPC.INI file, in the [HYPC INITIAL] section. Next time when Hypermet-PC starts, new settings will come into operation.

See also

   Using pop-up windows


Switching to Dual LFC corrected half

   If user collected a spectrum in Dual LFC mode, it is possible to display and evaluate it by selecting Options / Dual LFC / Uncorrected menu in Main module. Thus the uncorrected half of the spectrum will be displayed on the screen. To change between corrected and uncorrected half of the spectrum, user may click on the green button captioned UNCORR or CORR at the bottom of the screen, or may select appropriate menu under Options / Dual LFC. To switch between the two spectrum halves, user may select also Setting / Dual opt. / Corrected or Uncorrected menu in the Eval module.

See also

   LFC (Loss Free Counting method)

   Spectrum evaluation in Dual LFC mode


Switching to Dual LFC uncorrected half

   If user collected a spectrum in Dual LFC mode, it is possible to display and evaluate it by selecting Options / Dual LFC / Uncorrected menu in Main module. Thus the uncorrected half of the spectrum will be displayed on the screen. To change between corrected and uncorrected half of the spectrum, user may click on the green button captioned UNCORR or CORR at the bottom of the screen, or may select appropriate menu under Options / Dual LFC. To switch between the two spectrum halves, user may select also Setting / Dual opt. / Corrected or Uncorrected menu in the Eval module.

Note

  Be careful with Dual LFC option since it is also possible to display and evaluate by accident a non-Dual spectrum here . In this case the first or second half of the spectrum is hidden and only one half is displayed on the screen. If user does not recognise this mistake, then Hypermet-PC will produce erroneous results during spectrum evaluation. Switch off Dual LFC mode to check whether the loaded spectrum is measured in Dual LFC mode or not.

See also

   LFC (Loss Free Counting method)

   Spectrum evaluation in Dual LFC mode


Switching off Dual LFC mode

   To switch off Dual LFC mode, user should select Options / Dual LFC / Off menu (If it was previously switched on by selecting Options / Dual LFC / Corrected or Uncorrected menu).

Note

  Be careful with Dual option since it is also possible to display and evaluate by accident a non-Dual spectrum here. In this case the first or second half of the spectrum is hidden and only one half is displayed on the screen. If user does not recognise this mistake, then Hypermet-PC will produce erroneous results during spectrum evaluation. Switch off Dual LFC mode to check whether the loaded spectrum is Dual or not.

See also

   LFC (Loss Free Counting method)

   Spectrum evaluation in Dual LFC mode


Rubber band

   Rubber band is a very often used to scrutinise small parts of displayed spectrum in Hypermet-PC. This is a rectangle drawn with broken lines on the lower expanded window (when Expanded mode is on). While spectrum shown in details in the upper expanded window, rubber band shows the position of the magnified part in the whole spectrum. Furthermore, rubber band serves as a fast tool to change the position and the magnification of a spectrum detail displayed in the upper expanded window.

To modify rubber band with mouse:

- To change the position of the magnified spectrum detail, press and hold down the left mouse button in the rubber band and drag it to the desired position in the lower expanded window.

- To change the ratio of the enlargement, press and hold down the left mouse button outside of the rubber band in the lower expanded window and move the mouse pointer. Size of the rubber band changes accordingly to the movement of the mouse cursor. However, there are limits for height and width of the rubber band.

To modify rubber band with keys:

- To change the position, use the following keys:

  Alt+Left   Move rubber band to left

  Alt+Right  Move rubber band to right

  Alt+Up     Move rubber band to up

  Alt+Down   Move rubber band to down

- To change the magnification, use the following key combinations:

  Ctrl+Left  Collapse rubber band horizontally

  Ctrl+Right Enlarge rubber band horizontally

  Ctrl+Up    Enlarge rubber band vertically

  Ctrl+Down  Collapse rubber band vertically


Nuclid.std (calibration data file)
Nuclid.std

   The file "Nuclid.std" is a simple text file containing nuclear and certification data of selected radioactive sources (152-Eu, 182-Ta, etc. used for calibration purposes in Evaluation, Nonlinearity, Efficiency and FWHM Modules.  This file is user editable, but you must keep its fixed format.

   Hypermet-PC tries to load this file from current directory. If Nuclid.std is not found there, program tries to load it from the directory where Hypermet-PC resides.

   If this file not found or an error occurred during  load, you won't be able to use nonlinearity, efficiency, fwhm calibration modules and some features of Hypermet-PC will be disabled.

Notes:

1) only the strongest single gamma lines are entered in this file because it is essential for exact calibration. If you modify this file, be careful when selecting  calibrating gamma lines.

2) Nuclide ID module does NOT use data stored in Nuclid.std. Instead it uses a separated nuclide library stored in binary format.

See also

   Internal format of Nuclid.std

   Sample Nuclid.std file


Description of Nuclid.std format

   The file 'Nuclid.std' consists of two sections: gamma lines and radioactive source specifications. In every section there are more items with the same format.

Rules to interpret format description below:

- coloured text stands for literal text. e.g.: # means a hash-mark character

- text in angle brackets must not be omitted. e.g.: <nuclide name>

- text in square brackets are optional. e.g.: [d]

- 'abs.' denotes 'absolute'.

- 'unc.' denotes 'uncertainty'.

- see notes for additional rules.

Format description:

1)  First section describes the gamma lines of nuclides (which are appropriate for calibration purposes):

 #<nuclide name>   [;comment for nuclide]

 [T1/2: <half-life in days> <abs. HL unc. in days> [d]]

 <energy> <unc. of energy> <abs. intensity> <abs. unc. of intensity>

 <energy> <unc. of energy> <abs. intensity> <abs. unc. of intensity>

 <energy> <unc. of energy> <abs. intensity> <abs. unc. of intensity>

 …

  Example for gamma line data:

 #Am-241   ;IAEA-TECDOC-619 1991 Sept

 T1/2: 157861.05  0.7 d

  26.345   0.001     0.024    0.001

  59.537   0.001     0.360    0.004

2)  Second section describes certificates (sources) suitable for detector efficiency calibration.

- First a section-starter indicates that this is the second section:

 #CERTIFICATES:

- Next lines describes certificates and sources in them. It is possible to measure with a combined source (two or more nuclide in one certificate), but this is identical with the situation when nuclides are in separate certificates.

 #<certificate name>   [;comment for certificate]

 Nuclide:  <nuclide name>

 Activity: <activity> (<relative unc. of activity in percent>%)

 RefDate:  <time of activity measurement in mm-dd-yyyy hh:mm:ss format>

Example for certificate data:

 #Am85-264  ;OMH, Owner: A. Simonits

 Nuclide:  Am-241

 Activity: 421.2 (1%)

 RefDate:  10-01-1985 12:00:00

3)  You must close of Nuclid.std file with a single hash-mark (#) character:

 #

Notes:

  - Unit of energy is keV (1000 electronvolts).

  - Unit of activity is kBq (1000 Bequerels).

  - Unit of half-life: day  (3600*24 seconds).

  - Text lines should not be longer than 250 characters

  - Empty lines are allowed in every section.

  - Characters preceded with a semicolon (;) are treated as a remark.

  - Hash-mark character has a special meaning (section starter). Do not leave spaces after a hash-mark because this indicate the end of Nuclid.std file.

  - Nuclide name in a certificate record must be previously defined in  gamma lines of nuclides section and can contain only letters, digits, '_' or '-' characters.

  - In a certificate record it is possible to place more nuclides - however, this situation is treated as they were in their individual certificate record.

See also

   General information about Nuclid.std

   Sample Nuclid.std file


Sample Nuclid.std file

Following lines serve as an example for a Nuclid.std file (a small part only):

#Am-241   ;IAEA-TECDOC-619 1991 Sept

T1/2: 157861.05  0.7

  26.345   0.001     0.024    0.001

  59.537   0.001     0.360    0.004

#Ba-133   ;IAEA-TECDOC-619 1991 Sept +Deb88

T1/2: 3838.7775  18.2625             ;Comment

  79.6127  0.0015    0.0263   0.0008

  80.998   0.005     0.3411   0.0028 ;Comment

 276.398   0.001     0.0717   0.0004

 302.853   0.001     0.1832   0.0007

 356.017   0.002     0.620    0.003

 383.851   0.003     0.0893   0.0006

#K-40   ;NDS

 1460.75   0.06       10.6711    2.66778

#CERTIFICATES:

#Am85-264  ;OMH, Owner: Simi

Nuclide: Am-241

Activity: 421.2 (1.0%)       ;Comment

RefDate: 10-01-1985 12:00:00

#Ba85-211   ;OMH, Owner: Simi

Nuclide: Ba-133

Activity: 456.4 (1.5%)

RefDate: 10-01-1985 12:00:00

# ;signs the end of Nuclid.std file

See also

   General information about Nuclid.std

   Description of Nuclid.std format


Nuclide ID report file

   When nuclide identification  ends, user can generate a detailed report of results to the screen, to a disk file or directly to the printer. Default extension of Nuclide ID report files is *.NUR.

   Because the report file can be extremely long (several hundred Kbytes), we suggest that:

- Before you print it, check results using Report / Screen and decide whether it is useful to print the whole report or not.

- Reduce the size of the report by disabling certain unnecessary parts  using the Setting / Report menu.

- If you are absolutely sure  that some isotopes were incorporated  in the report by miscalculation, remove them  using Setting / Nuclides menu.


Nuclide ID setting file

   Nuclide ID module can retain parameters set in a session by  Nuclide ID setting files (default extension is *.NUS). User can save parameters applied in a nuclide identification process and reload them later to restore former Nuclide ID environment setting. This is especially useful if you have changed the range of nuclides involved in the analytical process and restoring the individual nuclide set manually would be a tedious process.

   To save Nuclide ID setting file, use Setting / Save, while for restoring them use Setting / Load menus.


Spectrum evaluation with Hypermet-PC

   Spectrum evaluation is a process in which Hypermet-PC determines peaks and their characteristics in the measured gamma spectrum collected with semiconductor detectors. Hypermet-PC applies a sophisticated spectrum evaluation algorithm for automatic fitting of complicated gamma spectra.

   The peak shape function of Hypermet-PC is the linear sum of a Gaussian and a Gaussian with exponential tail on the left side. On the other hand, a step function folded with the same Gaussian and a similarly folded "tail" function, resembling a sharp Compton edge, are added to the usual first or second order polynomial background function. The fit becomes nonlinear as long as parameters of the Gaussians and exponentials are allowed to vary.

   Fully automatic operation in Hypermet-PC means that the shape parameters for peaks and background are found by a nonlinear fit for each separate region in the spectrum using an initial first trial value for the peak width. (The latter is found by a square-root interpolation from the approximate widths of two distant peaks provided by the user as the only input.)

   In contrast with SAMPO and its derivatives the shape parameters are not retained but fitted again and again. Hence dynamic variations of peak shapes throughout the spectrum are automatically accounted for. Moreover, the tedious process of shape calibration so characteristic in SAMPO [SAMPO1,SAMPO2] and GENIE-PC [GENIE1] is not needed at all. It is merely sufficient to enter the positions and widths of two peaks, used anyway for energy calibration.

   Logbook concept in Hypermet-PC provides a convenient tool to solve fitting problems: after the entire spectrum fitted automatically, all the fitting details are stored in a database. User might check only the faulty fits marked by an asterisk in the logbook and thus can concentrate only on  serious fitting problems. The bad fits can be improved by manual interactions and the repeated fits (called refits in the Hypermet-PC terminology) are stored separately in the logbook. Therefore user can select the best fit for a specific region of the spectrum and the data of the selected region will be placed in the text format report files.

   To obtain detailed information about the fitting process, see fitting algorithm.

See also

   Typical steps of spectrum fitting process

   Peak fitting algorithm

   Spectrum evaluation in Dual LFC mode


Hypermet-PC fitting algorithm

   First, the evaluated spectrum is automatically split into smaller parts, the so-called regions in Hypermet-PC terminology. Regions are typically made up of a couple of ten channels. The limit of the maximum number of channels per region is set to 201.

   Fitting algorithm will find peaks in every region. If a maximum number of peaks per region (8) is reached, region is automatically splitted into smaller parts.

   Spectrum evaluation needs a rough peak width calibration as the only indispensable input from the user. This value is used during the peak searching process. Peaks are searched using a filtering function (negative smoothed second difference) which clears spectrum from high-frequency statistical noise and gives a characteristic value around peaks whose FWHM is approximately equal with the estimated FWHM. During  peak search a pre-set threshold is used to distinguish peaks from statistical fluctuations.

   If a peak is found, then non-linear least-squares fit is performed to determine the best shape of the peak(s) and the background. In general, the peak width is the same for all peaks in a region.

   A measure of the goodness of the non-linear fit is the chi-square. If convergence has been found to a minimum, algorithm tests chi-square: if it exceeds a pre-set limit the fitting process is terminated. If not, the residual is searched for additional peaks. Residual means the difference of the fitted value and the measured data. Where residual found to be the largest in the fitted region, an additional peak is inserted and the whole fitting process is repeated. Thus the algorithm tries to reduce chi-square by inserting  new peaks.

   The number of maximum tries to insert a new peak is limited according to the Try parameter in the Fit window of Eval module. In general   the Try parameter is set to 3.

   To revise fitting details, you can select any previously fitted region from the Logbook. If fitting results are perfect, a report file can be generated with details of fitted peaks. Fitting results flagged with an asterisk (*) in the Logbooks Region list probably mean a bad fit or a fit which can be improved..

See details of corrections in Manual correction of bad fits.


Peak position files

(ASC files for Eval module)

   Peak position files are intended to store positions and position uncertainties of peaks for typical spectrum evaluations. The ASC files are loaded in Eval module to the Logbook to provide suggested peak positions. The loaded peak positions are considered by the Hypermet-PC fitting algorithm as a proposal and they are very useful for mass evaluations, when peak positions change only slightly between different spectra recorded with the same spectrometer setting. Such a way the duration of the time consuming peak searching algorithm can be significantly reduced.

   ASC files may contain either position and absolute uncertainty values in channels or in keV units. An example for the content of a typical ASC file:

;This is  a peak position file in keV

;for Cs-134 measurements

 475.350  0.05	;Comment

 563.227  0.015

 569.315  0.015

...

   To load a peak position file, use Logbook / Peak menu and click on Load list press button when the Peak manipulation pop-up window appears. The loaded peak positions are directly placed in the logbook as if they would have inserted manually with the Logbook / Peak menu and with the Insert button.

   The newly inserted peaks are marked with a letter u at the end of listed rows on the peak manipulation pop-up window (which can be reached by the Logbook / Peak menu).

Note

- Do not confuse ASC peak position files with ASCII format spectrum files. The former is a peak position file which helps to speed up the mass evaluation process in the Eval module and contains peak position and peak position uncertainty value pairs in every row. The latter file type is intended to hold data of the measured spectra channel by channel and contains only one count for every row.


CSV report format

CSV = comma separated values (=comma delimited values)

   CSV format files contains only simple text rows, in which numeric and textual fields can be mixed and consecutive values are separated with commas. Text fields are enclosed in quotation marks (in this way you can save text fields which contain commas itself).

   CSV report format is especially useful when you want to process the output of a Hypermet-PC module in a spreadsheet application, such as Microsoft Excel. If you save your report in CSV file format, then most of todays spreadsheet application will automatically convert your report to a spreadsheet.

See also

   PTF file format


PTF report format

PTF  = Peak Table Format

   PTF format is defined by the Sampo-90 program for holding results of a spectrum evaluation, such as peak centroid position, peak area, peak width (fwhm) etc. Hypermet-PC generates output files compatible with this popular file format which play the same role like Hypermet-PCs Short Report or PeakList files. When saving Hypermet-PC spectrum and results files in Sampo-90 file formats (*.PTF with *.SPE) a full compatibility is established to ease further processing  with such programs as the KAYERO/SOLCOI NAA element concentration calculation package.

See also

   CSV file format


LFC: Loss Free Counting spectrum measurement method
What is Dual LFC?

LFC = Loss Free Counting spectrum measurement method

   The Loss-Free Counting (LFC) method provides the ability of performing real-time correction of system counting losses needed, for example, when measuring short-lived radionuclides in NAA. When the Dual LFC mode is selected, then Hypermet-PC performs special fitting on the tandem spectrum.

Evaluation of Dual LFC spectra

   The settings and the preliminary steps of the fitting are the same as in normal mode, but the HYPERMET always starts with a normal peak search and fit in the uncorrected spectrum even if the corrected spectrum is displayed.

   After the region has been fitted and the region and the peak parameters have been stored in the Logbook database, the program starts a new fit in the corrected part of the spectrum with the same region boundaries. In order to eliminate a number of spurious peaks, no peak search is performed in this region and the peak positions are read in from the database. For the LFC corrected spectrum the same relative deviation is expected as in the uncorrected spectrum.

See also

   Spectrum evaluation in Dual LFC mode

   Switching to Dual LFC corrected half

   Switching to Dual LFC uncorrected half

   Switching off Dual LFC mode


Spectrum evaluation in Dual LFC mode

   Dual LFC evaluation option provides an improved method to utilise all information gathered during a measurement.. In short, evaluation algorithm takes statistical information from the uncorrected part and uses these information during peak fitting  in the corrected spectrum part.

   In short and peaklist report files both sections appear  headed by 'UNCORRECTED' and CORRECTED. In Sampo-90 PTF output files peak areas are taken from the corrected while peak area uncertainties are calculated using the uncorrected spectrum part.

See also

   Spectrum evaluation

   LFC (Loss Free Counting method)

   Peak fitting algorithm


Directory of temporary files

   When running various tasks  on your computer, there is sometimes a need to create temporary files (which will be deleted later).

   It is necessary to know the  directory for placing these files. For example, temporary files should not be created on floppy disks.

To create a temporary directory you shall set 'TEMP' or 'TMP' environment variable in AUTOEXEC.BAT file, e.g.:

SET TEMP=C:\WINDOWS\TEMP    or

SET TMP=C:\TEMP

Notes:

1) If there is already a TEMP or TMP setting in your AUTOEXEC.BAT file, do not modify this setting (if specified path exists).

2) Do not place spaces before or after the equation sign.

3) If your computer issues an 'Out of environment space' message during start-up procedure, refer to MS-DOS help to increase the amount of environment space: type 'help' at DOS command prompt, select <CONFIG.SYS commands> topic and 'Shell' command. Under Windows95, you should modify memory properties of MS-DOS prompt. To achieve this, start MS-DOS Prompt, click on Properties button, then click on Memory tab. Set Initial environment to 'Auto'. Press OK button and close program.


Binary Hypermet-PC Library

   This binary format library (Standard.BHL) contains all nuclear data necessary to complete qualitative analysis of NAA and PGAA spectra.

The NAA part is created from the Radioactive Table of Isotopes (1986) and contains 2784 gamma lines of 189 isotopes.

The PGAA part is a filtered version of data tables of M. A. Lone et al., (M. A. Lone, R. A. Leavitt, D. A. Harrison, Atomic Energy Of Canada Limited, Chalk River Nuclear Laboratories) and contains 5851 gamma lines of 83 elements.

To make an analysis, this binary library must be placed into the directory in which Hypermet-PC resides.

See also

   Hypermet-PC Library Lists


Hypermet-PC Library Lists

   To make qualitative analysis of a spectra, user must have a  Binary Hypermet-PC Library. However, sometimes it is useful to browse library content by energies or by nuclides. To ease this task, we provided these two lists in simple text format. Contents of these lists are identical with Binary Hypermet-PC Library. Files are  NAA.HLL, NAA.HLE, for the NAA method and PGAA.HLL, PGAA.HLE for the PGAA method. HLL files contains a list sorted by isotopes or by elements, while HLE files contains gamma lines contained in appropriate libraries sorted by energy.

   In Nuclide ID module two menus are built in under 'Library' menu: Browse by energies and Browse by nuclides' to ease browsing tasks.

Note: These text lists are not essential to make an analysis. If you want to save disk space and don't want to browse nuclide library, you can delete them. If you decide to restore them, you can install Nuclide ID library package separately from the original Hypermet-PC installation diskette.

See also

   Binary Hypermet-PC Library


Residual window (Eval module)
Residual window

   In the residual window the residuals  (difference of the measured and fitted data) are displayed. In this window the residuals are normalised to sigma units and 1, 2 and 3 times the standard deviations of the data points are displayed as horizontal coloured stripes. User can easily judge the goodness-of -fit for a specific channel looking at the residual window which uses the standard deviation scale for the Y axis.

To display the residual window:

 1) Switch to the Logbook using Logbook/Region menu and click on View button. A previously fitted region will be shown.

 2) Click on the green button in right side of the cursor info bar labelled with SPECT. Residual window appears.

To hide the residual window:

  - Click on the same green button labelled with RESID or

  - Click outside of the residual window in the lower expanded window.

See also

   Eval module user screen


Setting (*.SET) files
Setting files (*.SET)

   The setting files used by Hypermet-PC are user-editable text files which follows the syntactical rules defined for Windows *.INI files. See Format of HYPC.INI file for details.

   The setting files stores calibration data for a specific spectrum file as well as a two-point energy and peak width calibration and parameters for the peak fitting algorithm incorporated in Eval module.

   Set files holds these data between evaluations because Hypermet-PC does not store calibration data in the evaluation log file (*.LOG) and in the case of repeated evaluation the user must be able to restore the exact values for the calibration points.

   The setting files may contain specific sections of HYPC.INI file.

The sections can be placed into a SET file:

Setting calibration: for two-point energy and peak width calibration, and for specifying default nonlinearity and efficiency file.

Setting experts: for fine tuning the peak fitting algorithm.

See also

   Overwriting of calibration data

   [SETTING CALIBRATION] section

   [SETTING EXPERTS] section


Overwriting of calibration data

   Hypermet-PC uses the following algorithm for overwriting the calibration data:

  - At program start, Hypermet-PC loads the calibration values placed into HYPC.INI file.

  - If user loads a spectrum, then the calibration data contained in the spectrum will have the highest priority and will come into operation. Note, however, that not every spectrum type contains calibration data.

   If user start Eval module and a default SET file is specified in the HYPC.INI file (SettingFile variable in the EVAL FIT section), then the calibration data specified in that default SET file is loaded which overwrites the old values.

   Please note that user can delete any sections from the default SET file, therefore, it is possible e.g. to load peak width calibration data while the energy calibration values remain unchanged. Another user-friendly feature is to configure Hypermet-PC to load automatically the default setting file. This can be achieved by specifying the default SET file name without specifying the path for the default setting file.  For example, if user sets the file name as

   SettingFile = default.set

then Hypermet-PC tries to load default.set file from the directory where the spectrum was loaded from (more precisely, from the actual directory). If user stores all spectra in separate directories and saved every SET file using this common name, then the process of loading calibration data become automated.

If user specifies the default setting name with an absolute path, then calibration data will be loaded from the specified file. This may be useful if user can apply common parameters for  all measured spectra.

Notes:

  - Because at program start Hypermet-PC searches the HYPC.INI file in the current directory, therefore user can create duplicates from this file in separate directories. For example, if two measuring setup are  in use, it is practical to store measured spectra in separate directories and to store two different INI files in that directories. When user starts Hypermet-PC from one of the two directories, then the appropriate settings will be applied.

  - When user loads a spectrum file in which energy calibration information has been stored, Hypermet-PC disregard the (literary) energy values specified in the HYPC.INI file and computes the position for the two peak according to the calibration data loaded from the spectrum. If user later loads a SET file, then its calibration data will be overtaken!

See also

   Setting files (*.SET)

   [SETTING CALIBRATION] section

   [SETTING EXPERTS] section


HYPC.INI file

   HYPC.INI is a user-editable settings file. To eliminate the tedious task of customising basic parameters every time when user starts the appropriate program module, Hypermet-PC obtains default values for different tasks from this file when the program starts.

   For example, the scale used for displaying spectra may be linear or logarithmic. If user prefer one of these displaying methods, it is possible to redefine the default mode by editing HYPC.INI file and changing the default display mode to the preferred value. Next time when Hypermet-PC is started, the loaded spectrum appears in the specified display mode.

   When Hypermet-PC starts, it searches for HYPC.INI in the current directory, where the user invokes Hypermet-PC from. If HYPC.INI file could not be found there, search is made in the directory where Hypermet-PC main program (HYPC.EXE) resides. If default HYPC.INI is deleted from this directory, then pre-set values take into effect.

   The scheme presented above ensures that if more than one user uses Hypermet-PC regularly, every user can save its own individual settings in different directories. Different users should then start Hypermet-PC from different directories to enforce different settings.

Please select a HYPC.INI section to get help on it:

  - Technical

  - Hypc initial

  - Eval fit

  - Setting calibration

  - Setting experts

  - Quality control

  - Printing

  - BMP colors

See also

   Format of HYPC.INI file


Format of HYPC.INI file

   User can assign values to symbolic variables in HYPC.INI file using very simple syntactical rules (which are identical with the rules applied for MS-Windows INI files).

   General format of INI files is the following:

[Section A]

Parameter1=Value1

Parameter2=Value2

…

;comment

…

[Section B]

Parameter3=Value3   ;comment

Parameter4=Value4

…

   As you can see, the variables may be set in HYPC.INI are grouped together, and these groups are called sections. Section names must be indicated with square brackets, and must be started at the first character position of a row. Parameter names are simple words, with an equal sign after the name. User should place the value for assigning to a parameter after the equation sign. The format of the value is depend on the type of the parameter (number(s), text, file name, etc.)

  It is possible to write comment lines to the INI file to ease the understanding of the purposes of the parameters. Comments starts with a semicolon (;), then the rest of the actual line will be ignored.

Note:

  If a parameter requires a binary value, then each of Yes, On, 1 or No, Off, 0 values are acceptable after the equation sign.

See also

   Description of HYPC.INI


TECHNICAL section of HYPC.INI

[TECHNICAL]

Win3x=No

   The [TECHNICAL] section controls the critical error handling routine of Hypermet-PC (this causes the well-known Not ready reading drive A:  Abort, Retry, Fail? message). Because the MS-Windows 3.x versions handle this event totally differently from MS-DOS or Windows95, user MUST set the Win3x variable to Yes if using this operating system, otherwise Hypermet-PC will crash when a critical error occurs.

See also

   Description of HYPC.INI


HYPC INITIAL section of HYPC.INI

[HYPC INITIAL]

InitialPath   = c:\hypc\spectra\

InitialPath   = d:\spectra\

LogDrawing    = on

ExpandDrawing = off

LineDrawing   = off

Residual      = off

DualOption    = off

UpperLogAdj   = 5.0

SpectrumType  = AccuSpec

This section controls the majority of the default values for displaying and file-handling tasks.

InitialPath is the directory where Hypermet-PC will try to load spectra from. It can be multiply set with more drives in consecutive text rows. During HYPC.INI processing, the program will set the directory specified for the actual drive. Therefore the drive which is set in the last row will be the default drive (in the example above the default path will be set to d:\spectra\).

LogDrawing sets the initial spectrum display scale to logarithmic or to linear.

ExpandDrawing switches on the expanded spectrum display mode. See also: Main module user screen.

LineDrawing controls the displaying mode of counts. If it is on, then only a line is drawn between the maximal and minimal count which should be displayed in the same horizontal pixel of the screen. If it is switched off, then every count will be indicated with individual points on the screen.

Residual controls the opening of the residual window in Eval module. If it is on, then residual window automatically appears when user opens the logbook, otherwise it should be manually displayed with clicking on the SPECT green button at the bottom of the screen.

DualOption switches on or off the Dual LFC option for the loaded spectra automatically. If user set this variable to On, then every spectrum will be displayed in Dual LFC mode until user switches off the LFC mode in Main or Eval module.

UpperLogAdj: the larger this value, the less logarithmic the plotted spectrum is in the upper expanded window in Main or Eval module (when  expanded mode is switched on). The range for this value can extends from 1 to 10.

SpectrumType controls which spectrum type offered automatically at spectrum load. Possible values: S100, AccuSpec, Ortec, Sampo90, GeniePC, Nucleus, Silena, ASCII, DCHYP.

See also

   Description of HYPC.INI


EVAL FIT section of HYPC.INI

[EVAL FIT]

Try  = 3

Auto = off

Fix  = off

ROI  = off

PeakAddError= 0.5

;SettingFile = default.set

;SettingFile = c:\spectra\default.set

This section stores parameters for spectrum evaluation algorithm.

Try is the maximum number of tries, when Hypermet-PC will insert a new peak into the evaluated region at the position obtained by searching the maximum residual in order to improve the chi-square value for the fit. Minimum value is 1, maximum is 4. In general, Try=3 is acceptable for almost every region.

Auto holds the state of the Auto check box in the Fit pop-up window, thus controls whether Hypermet-PC evaluates automatically all the remaining regions in the spectrum (Auto = Yes) or stops after evaluating the current region.

Fix contains the initial value for Fix check box in the Fit pop-up window, thus determines whether boundaries of the actual region should be set automatically (Fix = No), or the fitting algorithm must use the fixed region boundaries set by the user. User can set manually the region boundaries by clicking with the right mouse button in the upper expanded window and sweeping over the preferred background holding down the mouse button. This region fixing works only if the user opened the logbook by Logbook / Regions menu.

ROI controls the ROI check box in the Fit pop-up window. Therefore, user can switch on this check box  to set ROI variable to On. In this case the fitting algorithm searches peaks only in the pre-set areas of ROIs.

PeakAddError sets the uncertainty of the peak position which is inserted by the user into a multiplet. The value should be given in channels.

SettingFile controls the automatic handling of setting files. The value assigned to this variable is the name of a settings (*.SET) file. User can place variables to the settings file which affects energy and FWHM calibration. Because user can specify the file name with or without absolute path (path with drive letter and full path), therefore user can perform sophisticated parameter setting strategies for different purposes. By default, Hypermet-PC does not use this parameter. For details about Setting files, see SET files.

See also

   Description of HYPC.INI


SETTING CALIBRATION section of HYPC.INI

[SETTING CALIBRATION]

Fwhm1    =  493.98,    3.8

Fwhm2    = 2035.24,    4.4

Energy1  =  493.98,  344.28

Energy2  = 2035.24, 1408.02

EcalMode = 1

;NonlinFile     = c:\hypc\det1\nonlin.lin

;EfficiencyFile = c:\hypc\det1\eff.eff

   This section provides default values for a two-point energy and FWHM calibration, and default files for nonlinearity and efficiency correction.  Please note that this section can appear in SET files.

Fwhm1 is variable containing the FWHM calibration data for the first calibration point of the two-point FWHM calibration. After the equation sign there are two numbers, the first is the channel number where the calibration point is taken from, while the second one is the approximate FWHM value for the peak which is found at the specified position.

Fwhm2 serves the second data point for the FWHM calibration line. Note that the FWHM function changes by the square root of the peak energy.

Energy1 sets the first calibration point for the energy calibration. User should specify the channel number - energy value pair after the equation sign.

Energy2 sets the second data point for the linear energy calibration line.

NonlinFile specifies the default nonlinearity file for the system. If the user starts Eval module, then Hypermet-PC loads this nonlinearity file and switches on nonlinearity correction. This may increase the precision of the energy calibration.

EfficiencyFile specifies the default efficiency file for the system. If the user starts Eval module, then Hypermet-PC loads this efficiency file and switches on efficiency correction. Saving a peaklist from the Eval module, the peaklist file will contain intensity data instead of peak areas. Intensity is computed as peak area divided by the detector efficiency and by the measuring time resulting in cps value at a given peak energy.

EcalMode sets the applied energy calibration method. If it is set to 0, then the energy calibration is disabled. In this case the positions of peaks will  be indicated  only in channels. If the variable is set to 1, this means a two-point energy calibration at the pre-set calibration positions. If value of EcalMode is set to 2, then Hypermet-PC replaces the specified energy calibration points with the positions of the closest fitted peaks in the spectrum. Therefore user can ensure a proper energy calibration for a series of measurements even if there is a minor peak shift in spectra..

See also

   Description of HYPC.INI


SETTING EXPERTS section of HYPC.INI

[SETTING EXPERTS]

Nought = 0.3, 0.5, 1.0, 1.0, 0.1, 1.0

Max    = 2.0, 2.0, 1.3, 0.1, 3.0

Min    = 0.2, 0.2, 0.7, 2.5, 500.0

N      = 0, 0, 0, 0, 0, 0, 0, 0

Sigma  = 4.0, 3.0, 6.0, 3.0, 3.0, 4.0

Limit  = 0.10, 1e-06, 1e-06, 1, 150

   This section of HYPC.INI is intended for experts only. It contains initial values for the peak fitting algorithm which controls the process of the spectrum evaluation. We provide an extensive listing here to help interpret the above values.

HYPERMET PARAMETERS

Fitting Function for Channel L, Region NREG:

Y(L) = sum over of peaks I of SUPRF(I,L) + TAILF(I,L) + BACK(L)

SUPRF(I,L) = GAMMA(I) * EXP( -(X(I,L)/DEL(I))**2) + AGAMM(I) * EXP(X(I,L)/BDELT(I)) * 0.5 * ERFC( X(I,L) / CDELT(I) + 0.5*CX / BX )

TAIL(I,L) = SGAMM(I)*ERFC( X(I,L) / SDELT(I) ) + TGAMM(I) * EXP(X(I,L)VDELT(I)) * 0.5 * ERFC( X(I,L) / UDELT + 0.5 * UX / VX )

BACK(L) = AVEL + RATE*L + CURV*L*L

Where

    X(I,L) = L - PL(I,NREG)

    AGAMM(I) = AX*GAMMA(I)

    SGAMM(I) = STEP * GAMMA(I)

    TGAMM(I) = TX*GAMMA(I)

    BDELT(I) = BX*DEL(I)

    CDELT(I) = CX*DEL(I)

    SDELT(I) = SX*DEL(I)

    UDELT(I) = UX*DEL(I)

    VDELT(I) = VX*DEL(I)

    DEL(I) = WIDTH(I) / 1.66511 = WIDTH(I) / (2*SQRT(ALOG(2)))

SX and UX are fixed, CX may be fixed or = CO * BX (see NCB below), DEL(I) is normally held equal for all I, and all variable parameters are constrained by maximum and/or minimum limits.

Area for Peak

   AREA(I) = integral of SUPRF(I,L) from minus infinity to infinity allowing L to vary continuously.

which gives

   AREA(I) = GAMMA(I) * (RPI + AX*BX*EXP(-(0.5*CX/BX)**2)

where RPI = 1.772454 = SQRT(PI)

The meaning of the parameters in the [SETTING EXPERTS] section are the following:

NOUGHT: A0, B0, C0, ST0, U0

  Initial values for AX, BX, CX, SX, STEP, UX, respectively. The initial width is calculated on the rough peak width calibration. Initial values for TX, VX (and usually STEP) are calculated.

MAX: AMAX, BMAX, WMAX, TMAX, XMX

  Maximum values for AX, BX, WID, TX, respectively. AMAX, BMAX, WMAX, are relative to their initial values. TMAX is relative to the peak height GAMMA. XMX controls the region IMX above a peak which will be searched for additional peaks, IMX=2*NWID*(XMX+BO).

MIN: AMIN, BMIN, WMIN VMIN, GMIN

   Minimum values for AX, BX, WID, VX, respectively. AMIN, BMIN, WMIN, are relative to their initial values. TMIN is relative to WID. GMIN = the minimum peak height for inclusion of a STEP and/or TAIL.

N: NA, NB, NW, NCB, NCV, NST, NTV, ICS

  NA, NB, NW nonzero fix AX, BX, WID, respectively. NCB nonzero sets CX = C0*BX.  NCV, NTV nonzero eliminates CURV, TAIL, respectively. NST positive eliminates both STEP and TAIL. NST = -1 fixes STEP = initial value calculated from the spectrum, NST = -2 fixes STEP = ST0, NST = -3 fixes STEP = 0.  ICS nonzero allows widths to vary independently.

SIGMA: SIG, RSIG, CSIG, TSIG, XSIG

  Threshold for statistical tests, units of one standard deviation. SIG = threshold for detection of a peak in SEARCH routine. RSIG = threshold for detection of a peak in RESIDUAL test. CSIG, STIG, TSIG = threshold for inclusion of CURV, STEP, TAIL, respectively. XSIG = upper limit for CHISQUARE test.

LIMIT: FEST, GEST, IEPS, ITLIM, MAXFN

  Criteria for termination of a fit in Subroutine FLETCHER.

  FEST = convergence criterion for the function F = CHISQUARE / 2.

  GEST = convergence criterion for the gradient G of F.

  CEPS = constant convergence criterion for the parameters X.

  IEPS controls the use of CEPS or IPS0 (below) to calculate convergence criteria EPS(J) for the parameters X(K).

     IEPS = 1, EPS(K) = EPS0( J(K) )*X(K).

     IEPS = 2, EPS(K) = CEPS*X(K).

     IEPS = 3, EPS(K) = CEPS.

  ITLIM = maximum number of iterations.

  MAXFN = maximum number of function evaluations.

 (This description is obtained from [PHILMARL]).

See also

   Description of HYPC.INI

   Hypermet-PC fitting algorithm


QUALITY CONTROL section of HYPC.INI

[QUALITY CONTROL]

DegreeOfPol = 6

Residual = chi

Grid = on

   This section contains common settings for Quality Assurance modules, such as Nonlinearity and Efficiency calibration.

DegreeOfPol sets the default order for the polynomial function applied in the fit of nonlinearity or efficiency curves.

Residual sets the default type of the lower residual window for the nonlinearity and efficiency modules. Available values are: none, chi, difference for hiding the residual window, for displaying the residual in chi units, for displaying the residual in keV units, respectively.

Grid controls whether the horizontal and vertical gridlines are displayed by default or not. If this variable is set to On, then grid will be switched on automatically.

See also

   Description of HYPC.INI


PRINTING section of HYPC.INI

[PRINTING]

Printerport=1

This section controls the printing properties. Because Hypermet-PC prints simple text files without any formatting and sends data directly to one of the parallel ports built-in into your computer, the section provides only one variable to specify: the printer port.

PrinterPort variable sets the printer port to which Hypermet-PC will send data. After the equation sign, a figure 1 should be specified for LPT1 port, 2 for LPT2 and so on.

See also

   Description of HYPC.INI


BMP COLORS section of HYPC.INI

[BMP COLORS]

black        = 255  255  255  ;white

blue         = 0    255  255  ;cyan

green        = 0      0    0  ;black

cyan         = 128  128    0  ;khaki

red          = 128  128  128  ;grey

magenta      = 255  255  255  ;white

lightgray    = 128  128    0  ;khaki

brown        = 0    128  128  ;greenish blue

darkgrey     = 0    255  255  ;lightcyan

lightblue    = 0      0  255  ;blue

lightgreen   = 0      0    0  ;black

lightcyan    = 192  192  192  ;lightgray

lightred     = 0      0  128  ;darkblue

lightmagenta = 255  255  255  ;white

yellow       = 0      0    0  ;black

white        = 0      0    0  ;black

   This section defines the converting scheme for screen colours when saving screen to a Windows bitmap file (using hotkey <Alt-P>). Under the section name, one or more of the 16 colour names should be specified as the name of the variable. Every variable defines the remapping of the pixels drawn with the actual colour on Hypermet-PC screen. The resulting colour should be defined with a triad of values extends from 0 to 255, for red, green and blue colour components, respectively. The numbers defines the intensity of R,G,B colour components in the compound colour.

   For example, if user wants to convert the black on Hypermet-PC screen to white in the stored bitmap picture, place the following line under the section name:

   black = 255 255 255

   The line above means that convert black to a specific colour which has maximal intensity in red, green and blue (this is the white colour).

   If you don't want to change a specific colour in the bitmap file, remove the entire line concern the colour or place a semicolon before the colour name.

   If you want to save the screen as it is without any colour arrangement, then remove the whole section from HYPC.INI or place a semicolon before the section name:

;[BMP COLORS]

black = 255 255 255

…

   Therefore user can create different colour schemes for different purposes. The default scheme presented in the distributed HYPC.INI file is ideal for printing on black and white laser printers.

See also

   Description of HYPC.INI

   Format of HYPC.INI file