ORTEC GammaVision-32 V5.2 Gamma spectroscopy, GEM 100% Ge Detector, CFG-PV-1 Vertical Cryostat, DWR-30 Dewar, DSPEC PLUS Digital Spectrometer, 138-G Marinelli Beaker How-To Guide

ORTEC

®

GammaVision-32 Version 5.2 How-To Guide:

Make Gamma-Ray Measurements Today

GammaVision-32 V5.2 is an integrated gamma spectroscopy data acquisition and spectral analysis software program that operates with the ease of the Windows-based operating system environment.

By reading in this How-To guide, you will learn the basics of GammaVision and begin making simple gamma-ray measurements. You will need a Standard Source (and the certificate information) for the calibration exercises carried out in the example.

System used for this How-To Guide

GammaVision is a dynamic software package that is capable of recognizing a number of hardware configurations. The software is designed not only to determine the hardware that is connected, but also to enable only those features of GammaVision that are supported by the hardware that you have connected.

GammaVision-32 V5.2 can support any mixture of the following types of units (with proper hardware configuration and installation): 916A, 917, 918A, 919, 920, 921, 926, 92X, NOMAD™ Plus, NOMAD,

MicroNOMAD ® , OCTÊTE PC ® , TRUMP ® , TRUMP-PCI, MicroACE™, DART ® , DSPEC ® , DSPEC Plus™, 92X-II,

MatchMaker™, M

3

CA and other modules. The DSPEC Plus Digital Spectrometer was chosen for this How-To

Guide due to the increasing popularity of this state-of-the-art product.

Components used for creating this How-To Guide

Item

GammaVision-32 V5.2

Ge Detector GEM 100%

Vertical Cryostat

30 Liter Dewar

Lead (Pb) Shielding

Digital Spectrometer

Interface

Computer

Calibration Source

2-L Marinelli Beaker

ORTEC Model No.

A66-B32

GEM100

CFG-PV-1

DWR-30

NA

DSPEC-PLUS

Description/Function

Gamma spectroscopy analysis software

High-resolution gamma-ray detector

Cooling unit & housing for detector

Liquid nitrogen (LN

2

) holding tank

Pb bricks with copper liner

Digital spectrometer and MCA (contains HV bias supply for detector and Ethernet Computer interface)

ETHCBL1 or ETHRJ45 Ethernet connection (10Base2 coax and 10BaseT

NA

NA

RJ-45 to coax converter)

Windows 98, Pentium 233 64MB Memory

2-L Marinelli Beaker geometry purchased from

Analytics, Inc., Atlanta GA

NA Model 138-G.Purchased from GA-MA Associates,

Miami FL.

Using This How-To Guide

Information in this How-To Guide is restricted to the most relevant tools needed to begin using your system.

Calibration basics, theories and fundamentals are touched on only to make clear the purpose of a given task.

There are a number of important steps required for an accurate calibration. By following this How-To Guide, you will familiarize yourself with these steps, and the steps needed to calibrate your system for almost any sample matrix and geometry.

In the example exercise, we highlight the features of GammaVision needed to begin analyzing samples quickly. We assume that your system is powered up and connected to a compatible PC and you have correctly installed the GammaVision software. In the example, we analyze 2-L ground-water samples in a

Marinelli-beaker geometry. The sample was collected from a seasonally anoxic lake in the Southeastern

United States. Our analyte of interest is Cs-137, with a primary gamma-ray full-energy peak of 661.7 keV. To make these gamma-ray measurements, you will need to accomplish the following tasks:

• Calibrate the detector (energy, efficiency, and peak shape)

• Count your sample

• Analyze the spectrum

• Create a report

To best use this How-To Guide, it is recommended (for the first-time user in particular) that the steps be followed in order from start to finish.

1.0 Calibration

Some things you should know

You need to calibrate your system for three basic parameters:

• Energy vs. Channel Number

• Efficiency

• Full-Width at Half Maximum (peak shape)

Energy vs. Channel Number

When a gamma-ray (photon) is absorbed by a germanium detector, a small signal (often termed a pulse) is produced. The signal is amplified and filtered in such a way as to reduce noise and produce a "clean" signal.

The magnitude of the net signal is proportional to the energy of the photon (i.e., photons with greater energies produce larger pulses). A device called an Analog To Digital Converter (ADC) is used to convert each pulse into a channel number (larger pulses will be converted into a higher channel). Each pulse is registered as a count in a unique channel by the Multichannel Analyzer (MCA). The result is a histogram of pulses (called a spectrum) displayed as counts in channels in the MCA emulator window of GammaVision. As pulses are received and processed, GammaVision continuously shows the resulting spectrum. Since the system has no advance knowledge of the energy of the incident photons, an energy calibration is performed to assign the correct energies to appropriate channel numbers. The energy calibration is performed by counting a standard source with known nuclide energies and instructing GammaVision to define channel numbers in terms of known energies. This information is then used to evaluate unknown spectra.

Efficiency Calibration

Only a fraction of the photons emitted from your sample will be registered as counts. This fraction (known as the efficiency) is primarily a function of the energy of the emitted photons, source geometry, size of the detector and sample composition. The efficiency is determined by counting a standard source of the same composition and geometry as your samples. The standard source should consist of a suite of nuclides with energies that will include all nuclides of interest for your measurements. In our example, we will use the autocalibration feature of GammaVision to calibrate energy and efficiency of the system.

Peak Width Calibration

The width of gamma-ray peaks depends upon a number of statistical uncertainties involved in the processes of collecting and transmitting the gamma-ray signal to the MCA.

1,2 Knowledge of the change in peak width with increasing energy is necessary for measurement of peak area and for peak fitting. By convention, peak width is measured by Full Width at Half Maximum. GammaVision allows the user to calibrate peak width using the same spectrum as energy and efficiency. In this example, the auto-calibration feature is used for peakwidth calibration.

Calibration — Getting it Done

1.1 Fit the calibration source on the detector endcap and close the shield. In this example, a 2-L Marinelli beaker standard source was used. The standard matrix is an epoxy with a density of 1.0 g•cm –3 (the density of water). The water samples to be analyzed must use this same 2-L Marinelli beaker geometry and be the same density.

1.2 From the Windows desktop, click Start, Programs, GammaVision-32,

GammaVision (Fig. 1). This will invoke the GammaVision software. Your view will be of the Multichannel Analyzer (MCA) emulator window. The MCA emulator window is the main interface for working with GammaVision. There are nine menus to choose from:

• File

• Acquire

• Calibrate

• Calculate

• Analyze

• Library

• Services

• ROI

• Display

1.3 Choose Acquire, Start to begin counting your standard source (Fig. 2). Count until there are well-defined peaks visible in the main window. Choose Acquire, Stop.

Fig. 1

1.4 Look at the spectrum you have acquired. To change the display (e.g., fill colors and Region of Interest shading), choose Display, Preferences, and select one of the options. For this example, we will select the Fill All option from the Preferences submenu (Fig. 3). The resulting spectrum contrasts the background in this example.

Use the thumbnail feature in the upper right corner of the main spectrum window to move from one part of the spectrum to another by left-clicking and dragging the mouse (Fig. 4).

Fig. 3

Fig. 2

1.5 Locate a full-energy peak (a clear sharp peak) in the main part of the MCA spectrum and use the Zoom feature to look more closely at the structure of the peak. There are three ways to use the Zoom feature. First, try the menu approach. Drag the thumbnail until the peak of interest is roughly in the middle of the thumbnail.

Click on the peak in the main MCA window. Click

Display, Zoom In to move closer (Fig. 5).

Continue to move closer by clicking the Zoom In control button on the GammaVision tool bar (Fig.

6). Zoom out from the peak of interest using the same methodology. You can also use the functions keypad<+> (to zoom in) and

keypad<–> (to zoom out). In most cases, the

Number Lock on the computer keyboard must be enabled to use the keypad features.

Fig. 4

Note: As mentioned above, an important parameter in accurate gamma-ray measurements is the shape of the full-energy peaks. In order to correctly portray the peak width, the transformation of pulses to counts in the MCA must be optimized. This is accomplished manually by adjusting the pole-zero feature in the system. GammaVision automates this procedure using a computer algorithm located in the MCB Properties submenu in the main

Acquire menu. In this example, a DSPEC Plus digital spectrometer is used.

1.6 To optimize the shape of the gamma-ray peaks for your system, choose Acquire, MCB

Properties, and click the Amplifier tab. Adjust the

Fine Gain to 0.67 and choose X1 for the Coarse

Gain (Fig. 7). Click the Optimize control. In a few moments the computer algorithm will automatically adjust the pole-zero feature of the DSPEC Plus.

You will be alerted when the process is complete.

Note: Inspect closely one of the full-energy peaks by using the Thumbnail and Zoom In features as described above. A well-shaped gamma-ray peak will be "gaussian" in shape (roughly symmetric about the centroid). The base of the peak will be slightly higher on the low energy side of the peak due to a phenomenon known as Compton

Scattering. For a full explanation of this phenomenon, consult the texts in the Reference section of this How-To Guide.

Fig. 5

Fig. 7

Thumbnail

Fig. 6

1.7 The first step in the energy calibration is to collect a spectrum using a standard source consisting of nuclides with known energies. The length of the count will be dependant on the count rate in the peak-energy regions of your standard calibration source and the counting statistics that you would like to achieve. A good rule of thumb for the number of counts in the full-energy peak region (for calibration) is 100,000 (0.3% counting statistics). GammaVision allows you to preset a limit for the count time (real time or live time), peakcentroid counts, or Region Of Interest (ROI) integrated counts.

1.8 To determine the needed count time, choose Acquire, Start. Count for several minutes, then choose Acquire, Stop. Here you will use the embedded features of GammaVision to determine the number of net counts in a Region of Interest (ROI). Place the cursor to the left of the peak of interest. Left click and drag the cursor across the energy peak — a box will appear as you drag the cursor (Fig. 8A). Once the box encompasses the entire width of the peak, stop and unclick. The box will remain in the window. Next, right click within the box and select Mark

ROI (Fig. 8B). The result is a highlighted ROI (Fig. 8C). To view the attributes of the peak, right click within the region and select Peak Info

(Fig. 9). An information box will appear that contains relevant information about the selected region (Fig. 10). In this example we find that the number of net counts (the area of the peak above the background) for the 1173 keV Co-60 peak is 3,302,351 counts — well in excess of the needed counts for good peak statistics

(<0.1% in this case) for an energy calibration. Repeat this exercise for other peaks of interest for your standard source. Scale the count time for your calibration to ensure good statistics for all the certified nuclides in your standard source.

Fig. 8A

Fig. 8B

Fig. 8C

1.9 Once you have determined the needed count time for your calibration, you will need to preset a value for the count time. Choose Acquire, MCB Properties,

Preset Limits. Click in the Live Time input box and type the desired Live Time (in seconds) for your calibration

(Fig. 11).

1.10 Choose Acquire, Start and allow the system to accumulate counts for the preset live time. When the acquisition is complete, choose File, Save and save the file to an appropriate working directory.

Note: There are three steps to conclude the calibration process:

Energy Calibration, Peak Shape Calibration (FWHM), and

Efficiency Calibration. Each step involves selection of peaks in the spectrum, input of known peak information, and archiving of the spectra and peak information. You will calibrate the energy first

(peak shape is also accomplished with this step). Next, save the energy calibration (.ent file) to the working directory, then calibrate for efficiency and save the efficiency calibration (.eft file). Finally, you will save the spectrum as a .clb file that contains all the calibration information needed to analyze your samples.

Fig. 9

Fig. 10

Fig. 11

1.11 Choose Calibrate, Energy (Fig. 12A).

Three new windows will appear — Energy,

Energy Table, and Calibr, (Fig. 12B). These windows may be selected and moved by leftclicking and dragging the upper colored part of each window.

1.12 From the Calibr window, choose the

Windows™ icon in the upper left-hand corner and scroll to Destroy (Fig. 13). This will eliminate any existing calibration information.

Fig. 12A

Note: GammaVision manages analysis information in the form of libraries. There are a number of libraries that are included with

GammaVision. For calibrations, the Calib library contains a list of common nuclides included in full spectrum calibration sources.

1.13 Choose Library, Select File (Fig. 14A). The Calib library resides in the User directory (by default). If you have moved the

Calib library, browse to the correct directory. Select the Calib library and click Open to load this library (Fig. 14B).

1.14 Choose Library, Edit, GammaVision Editor (Fig. 15). A window appears containing the nuclides included in this library (and the peak information for each peak).

1.15 Compare the list in the

Calib library to the list of nuclides contained in the

Standard Certificate for your standard source. You may delete nuclides from the list by highlighting the nuclide and selecting Cut (Fig. 16).

Fig. 13

Fig. 14A

Fig. 12B

Fig. 14B

Fig. 15

Fig. 16

1.16 To add a nuclide to the list, click Insert. Input the Nuclide Name, Half Life, and Uncertainty information (from the standard certificate) and click OK (Fig.

17). The check boxes in this window are designed to flag nuclides of your choice for reporting purposes. We’ll skip this for now.

1.17 Choose Auto Calibrate in the Calibr window to calibrate energy and

FWHM (Fig. 18A). The energy calibration table and a graphical representation of the fit will appear. The energy vs. channel fit should appear linear (Fig. 18B). If not, return to step 1.14 and carefully compare the list of nuclides in the library to the list of nuclides on your standard certificate — the energies must match.

Another way to check the energy calibration is to inspect the Delta values in the

Energy Table (Fig. 18C). These values are a measure of how well the calibration fits the actual data points. For a well-shielded system, the Delta values for a good energy calibration should be small — typically less than 1%.

1.18 Inspect the FWHM calibration by selecting

FWHM in the Calibr window. The table and graph will immediately display (Fig. 19). The trend for the FWHM is increasing with energy

— although non-linear.

Fig. 17

Fig. 18C

1.19 Save the energy calibration by choosing

Save in the Calibr window. Browse to the directory where you

Fig. 18A

Fig. 18B would like to store the energy calibration, name the file (a representative name is recommended), and click Save (Fig. 20). Click the

"X" in the upper right-hand corner of the Calibr window to exit the efficiency calibration workspace. The working energy calibration is now the file that you just saved — this includes FWHM and energy vs. channel number.

Fig. 20

Fig. 19

1.20 To begin the Efficiency Calibration, choose

Calibrate, Efficiency (Fig. 21). Next, click the Windows icon in the upper left-hand corner of the Calibr window and select Destroy (Fig. 22). This will eliminate any existing efficiency calibration information — the energy and peak width calibration will remain intact.

Note: In the next section, you will manually build an efficiency library and calibrate your system for efficiency vs. energy. In Steps 1.21 and 1.22 you will insert the peaks that you wish to include. For this procedure, be

sure to insert the peaks beginning with the lowest up to the highest energy.

1.21 Begin selecting the nuclides for the efficiency calibration beginning with the lowest energy peak in your nuclide list. In this example, Am-241 is the lowest energy nuclide in the 2-L Marinelli standard source. Move to the Am-241 peak by using the Peak selection tool on the righthand sidebar of the MCA window (Fig. 23).

Check the energy of each peak by clicking

Peak Info (as in Step 1.8) or by viewing the status line at the bottom of the MCA window.

1.22 Follow the following procedure for each peak selected: Choose Enter from the

Calibr window (Fig. 24A) — an entry will appear in the Efficiency Table. Select the

entry in the table

then click Calc

from the Calibr

window (Fig. 24B)

— the Efficiency

Fig. 24A

Calculation

Worksheet window will appear (Fig.

24C). Complete the form using the information from

Fig. 24C your Standard

Certificate and click Calculate Efficiency. When you have completed the form and the efficiency has been calculated, click OK to return to the MCA window.

Fig. 21

Fig. 25A

Fig. 24B

Fig. 22

Fig. 25B

Fig. 23

1.23 Repeat this procedure for each nuclide in your standard source that you wish to include in the efficiency calibration. Be sure to insert the peaks in ascending order by energy.

1.24 Once you have selected the peaks for your efficiency calibration, choose Polynomial from the Mode list in the Calibr window (Fig. 25A). The resulting fit should look similar to the one obtained in this example

(Fig. 25B).

1.25 To save the efficiency calibration, click Save in the Calibr window, browse to the working directory, name the file, and click

Save (Fig. 26).

1.26 Once the efficiency table file has been saved, exit the calibration by clicking the "X" in the upper right-hand corner of the Calibr window.

1.27 Next, save the complete calibration as a ".clb" file that can be recalled at any time for analyzing samples of this geometry and matrix (2-L water samples in the Model 138 Marinelli beaker geometry, see Step 1.1).

Fig. 26

1.28 Choose Calibrate, Save Calibration (Fig. 27A). Browse to the working directory, name the file (a representative name is recommended) and click Save (Fig. 27B). A dialog box will appear to allow you to input a detailed description of the calibration (Fig. 27C). Input the description and click OK.

Fig. 27C

Fig. 27A

Fig. 27B

2.0 Sample Type Setup — Libraries and Analysis Options

Note: GammaVision is designed with the flexibility to create many custom application analyses. The software includes four analysis algorithms — each with a unique capability. For this How-To Guide, we will use the

WAN32 analysis program. For a description of the analysis programs included in GammaVision, please consult the GammaVision-32 V5.2 User’s Manual.

GammaVision assembles the important parameters of gamma-ray analysis in one convenient Windows dialog environment called the Sample Type — in most cases a template is needed to allow the Operator to create one analysis for many samples. The parameters that often require customization include:

• Calibration

• Peak Library Data

• Report Output Requirements

• Decay Corrections

• Method of Peak Analysis

We will use the Sample Type environment to create a template to analyze 2-L water samples. These samples were collected (at varying depths, 0 to 9 m) from the water column of a small lake in the Southeastern United

States.

2.1 To begin, create a library which includes only the nuclides that we are interested in reporting for our analysis. From the main

MCA window in GammaVision choose

Library, Select File (Fig. 28A).

2.2 Browse to the User directory, choose the Calib library and click Open

(Fig. 28B).

2.3 Choose Library, Edit,

GammaVision Editor

(Fig. 28C).

Fig. 28C

Fig. 28A

2.4 Since we are interested in Cs-137 and a few other naturally-occurring radionuclides, we may delete several of the isotopes used for calibration. Save this library with a new name that represents the type analysis it will be used for. Click the

Windows icon in the upper left-hand corner of the editor and choose Save Library As (Fig. 29). Save the library with a representative name — in this example we call the library

"PondB".

2.5 To delete isotopes from the library highlight the isotope in the list (with a single click) and choose Cut (Fig. 30). Delete all of the isotopes in the library list except Cs-137 and Am-241.

2.6 To add nuclides to the library list, click the Windows icon in the upper left-hand corner of the editor and select Show Master

Library (Fig. 31). Choose the Suspect library list from the User directory and click Open (Fig. 32).

2.7 We will add Ra-226 and Th-234 to the library. Highlight Ra-

226 from the Suspect list (with a single click). Next, click Insert

Ra-226 in the PondB Editor Window (Fig. 33). Repeat this exercise for Th-234. Close the Suspect list by clicking the "X" in the upper right-hand corner of the window. Close the PondB library in the same way. You will be prompted that the library has been changed and asked to save the changes — answer yes to these questions and you will return to the MCA window.

Note: You have now completed the steps necessary to calibrate your system for three basic parameters:

• Energy vs. Channel Number

• Peak Shape (FWHM)

• Efficiency vs. Energy

Now, to create a template that can be applied to many samples.

We will apply the template to the analysis all samples in this group.

Fig. 28B

Fig. 29

Fig. 30

Fig. 32

Fig. 31

2.8 Choose Analyze, Settings, Sample Type

(Fig. 34A) to open the Analysis Options dialog window (Fig. 34B).

2.9 Select the Sample tab. We are creating a template to use for many samples — we will save this template as an ".sdf" file that can be applied to all our analyses. Click Save As from the Sample tab, browse to the working directory, name the file and click Save (Fig.

35).

Fig. 34A

Fig. 33

Fig. 34B

Fig. 35

2.10 Complete the Sample tab by performing the following

(Fig 36 can be used as a guide):

• Click Presets and place the cursor in the Live Time input box and type the number of seconds for your count — for this example input 86,400 seconds (a one-day count). Click OK and type in a description for your ample counts.

• Type in an Analysis Range From:200 To:16,000 and set

Random Summing to 0.

• Select the Auto Background Type.

• Click Browse to select the Nuclide Library that you created in Steps 2.1 to 2.7.

• Click Browse to select the Calibration that you saved in

Step 1.28.

• Uncheck the Internal check boxes for Nuclide Library and

Calibration.

2.11 Click the System tab and perform the following (Fig. 37 can be used as a guide):

• Fill in the Laboratory and Operator name fields.

• Choose the Traditional ORTEC MDA Type.

• Set Peak Search Sensitivity to "3".

• Complete the rest of the form as shown in Figure 37.

2.12 Click the Decay tab and complete the form as follows

(Fig. 38 can be used as a guide):

• Check the Decay Correction Collection checkbox (this decay corrects to the sampling date)

• Fill in a Date and Time.

Note: The During Acquisition checkbox decay corrects the sample for decay during counting. GammaVision also allows the user to decay correct during sampling (the Collection check box under Sample Collection). Since our analyte is Cs-

137 (t1/2 = 30.2 years), the corrections for our example are negligible — the sample was collected over a 30 minute time period and count time is about one day (much less than the

30-year half-life).

2.13 Click the Report tab (Fig. 39).

• Uncheck the four Reporting Options checkboxes.

• Choose Percent and Total under Uncertainty Reporting and 2-Sigma under Confidence level to report a 2-sigma confidence level uncertainty as a percent of the activity concentration (you may also choose to report uncertainties in activity units).

• Under Output, check Display Analysis Results and choose

Program. You must choose a text editor to display the results.

In this example, we have chosen NOTEPAD.EXE. Choosing these options invokes the NOTEPAD text editor and displays the report when an analysis is performed.

Fig. 36

Fig. 37

Fig. 38

Note: GammaVision has the ability to create numerous custom reports. The settings chosen here will generate a simple report for illustration. For more detailed reports, please consult the GammaVision-32 V5.2 manual.

2.14 Click the Analysis tab to choose an Analysis Method and additional uncertainty components.

• Choose the WAN32 Program under Analysis Method.

• Add any additional uncertainty components under Additional

Error — in the example, we determined that the volumetric measurements of our samples contributed a 2% uncertainty component to the total uncertainty. You may add a Random component in the Additional Error.

• Complete the rest of the form as shown in Figure 40.

Note: There are four analysis engines included in

GammaVision. Although these analysis engines incorporate the same fundamental constants and decay equations, each program treats the sample analysis differently. The WAN32 analysis program is a good choice for simple analyses with a relatively small number of nuclides. For a more detailed description of the GammaVision analysis engines, consult the

GammaVision-32 V5.2 User’s Manual.

2.15 The Corrections and Isotopes tabs will not be needed for this analysis — the check boxes should be left unchecked.

2.16 Since each sample is a slightly different volume (not necessarily the same as the standard source), the sample volume must be input. This may be accomplished by using the

Ask On Start or Ask On Save Options.

2.17 To instruct GammaVision to ask for the Sample Volume when the user Saves the spectrum — such as at the end of the acquisition, choose File, Settings (Fig. 41) and check the

Sample Size checkbox under Ask On Save Options (Fig. 42).

This will ensure that a value is input for this parameter for every sample and allow the user to create a template useful for many samples.

Uncheck the Sample Size for now — we will use the Ask On Start Option in Step

3 instead.

2.18 Check Integer.Spc under Save

File Format. The Integer.Spc format should be used in most cases. Consult the GammaVision-32 V5.2 User’s

Manual for a description of the file formats included in GammaVision software.

Fig. 41

Fig. 39

Fig. 40

Fig. 42

3.0 Sample Analysis and Reporting: Acquiring,

Saving, and a Simple Report

Note: When GammaVision performs an analysis, a number of reports are generated — some user driven, some automatic.

The default settings for archiving these reports is located (from the main MCA window) under File, Settings — choose

Directories to inspect the defaults (Fig. 43). To modify these settings, choose Modify from the Directories tab and browse to the directory of your choice.

For our example, we chose to display the reports, but not to archive the reports (Step 2.13) — we could have easily chosen to create a report, display it for review, and archive the report in a user-defined directory in Step 2.13.

Fig. 43

3.1 Fit your sample on the detector in the same manner as the standard source used for calibration. In this example, we are analyzing six water samples for Cs-137. The sample analysis and reporting characteristics that are common to all of the samples are included in the Sample Definition File (.sdf) created in Step 2.

The Live Time Preset was set in Step 1.9 (Acquire, MCB Properties). Next, we will set up an automated dialog that will guide the user through input of the parameters that are unique to the individual samples in this group. These characteristics include:

• Sample Description

• Sample Size

3.2 To setup the user dialog for input of these unique sample parameters, choose

Acquisition Settings (Fig. 44). If the

Sample Definition File created in Step 2 is not selected in the input box, browse to the

Fig. 44 file location and choose open. Place a checkmark in the boxes for Sample Description and Sample Size and click

OK (Fig. 45).

3.3 Select Acquire, Start. Dialog boxes will appear, which require user input for sample information prior to the start of the acquisition (Fig. 46A, B). Input the information for each dialog box and click OK. The information is now stored with the spectrum for analysis. Once the input parameters are complete, the count will begin.

3.4 Upon completion of the count, choose

Analyze, Entire Spectrum in Memory (Fig.

47). The Sample Definition File stored all analysis option parameters that were created in Step 2. A report will be generated on the screen — this action will invoke the Notepad software to create the report that was setup in

Step 2.13 (Fig. 39).

Fig. 46B

Fig. 45

Fig. 46A

Fig. 47

3.5 The report contains all relevant data and information about the calibration, collection date and time, spectral analysis program, and a summary of the activities of the nuclides in the PondB library that was created in Step 2 (Fig. 48A, B, C).

Fig. 48A

Fig. 48B

Fig. 48C

Figure 48. Excerpts of information included in the report that was created in Step 2. The report contains

Sample Identification information (Fig. 48A), calibration data (Fig. 48B), and a summary of the activity concentration of the nuclides of interest (Fig. 48C).

Congratulations! By following this How-To Guide, you have completed a number of the steps needed to make gamma-ray measurements using GammaVision-32 V5.2. You have also familiarized yourself with a number of the important features and tools that will make implementing GammaVision for your application simpler and faster.

Reference

(1) Gilmore, G. & Hemingway, J. D. (1995), Practical Gamma-Ray Spectrometry, John Wiley and Sons, NY,

NY.

(2) Knoll, G. F. (1989), Radiation Detection and Measurement, Second Edition, John Wiley and Sons, NY, NY.

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HOTLINE 800-251-9750

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