Operational Training on the Spectra Evaluation Software Identify

1. Operational Training on the Spectra Evaluation Software Identify

2. Outline • About Identify • User interface • Necessary Settings (geometry, detectors, libraries) for identification • Results displayed on the info screen • Identified Isotopes and their confirmation • Spectra evaluation for different detectors (IdentiFINDER, portable liquid cooled HPGe and micro-detective, AT6101 backpack)

3. Identify by GBS-Elektronik • Requires expertise in gamma spectrometry • Identification based on peak search algorithm and comparison with isotopes/peaks in a library • Main features: • Freely configurable isotope identification tool: 20 gamma detectors, various absorber materials and nuclide libraries • Identification result provides list of isotopes with confidence levels (certain, uncertain and very uncertain) and activity estimation • Built in spectra simulator for visual confirmation of identification result • Training here includes less than 50% of the programs capability

4. Working with Identify – spectra evaluation • Load spectrum file (*.spe or *.chn format) • Configure settings: • Select detector (HPGe, CdZnTe, NaI(Tl), LaBr3) and detector size • Implement measurement distance • Implement absorber material and thickness • Select task and detector specific isotope library • Start peak search and nuclide identification  list of isotopes with different confidence levels • Confirm presence of isotope(s) by spectra simulation

5. Identify user interface • Menu bar for open/save file, selection of settings, language selection, … • Info display to get information about cursor position, selected library, peak search results and identified nuclides • Spectrum display to show selected spectrum • Cursor buttons to shift spectrum, zoom in/out around position of the fix cursor • Info field displays measurement time, energy calibration, detector’s resolution, used nuclide library, spectrum file name and folder

6. Menu bar Info buttons Info display Cursor buttons Info field Spectrum display cursor

7. Menu\settings\general • Display of the spectrum and calculations • Vertical axis (lin/log/sqrt/dlog) • Spectrum with/without background correction • Calculation of the peak search algorithm • Peak search parameter: • search sensitivity and search resolution, • energy variation by temperature • Report options: • Enable showing uncertain and very uncertain nuclides • Enable activity calculation • Show escape peaks, nuclide info, ….

8. Menu\settings\general Peak Search setup Display of spectrum Report options Subprograms Printer setup

9. Menu\settings\detector function • Standard settings: • Select detector which matches best to the equipment recorded the spectrum (1.) • Confirm with ‘use this detector’ (2.) • Detector geometry: • Detector specific data based on the selected detector (no input required) • Measurement distance (3.) • Radiation window: • Detector window material and thickness • Absorber and matrix • Absorber material and thickness for one or two shielding components (4.)

10. Menu\settings\detector function Detector window setting(goes atomatically with 1) Detector details (goes atomatically with 1) Absorber and matrixsetting 4. Distance setting 3. 2. 1. Select one out of 20 detectors

11. Menu\settings\edit library • Select and use an existing isotope library • Manipulate library: • Add isotopes from a master library • Delete isotopes from selected library • Add or delete single gamma lines of an isotope • Selection of gamma lines • Manually selection • Automatic large selection or small selection according to decay probability • At this stage exclude X-ray lines

12. Menu\settings\edit library Selected nuclide library Activatedgamma lines of selected isotope All gamma lines of selected isotope Preselection of isotopes by halflife, decay mode and mass number Master nuclide library

13. Menu\settings\edit library Add selection to isotope ‚Large selection‘ of gamma lines based on decay probability

14. Menu\settings\edit library • How to create a new library? • Select library which matches best • Manipulate library • Save as ‘new name’ • Check new library with existing data (isotope collection)

15. Info buttons and info display – cursor info • Information about cursor position • If cursor is placed within a gamma peak the following information is available: • Centroid and FWHM • Peak area with area error and peak rating • Nuclides assigned: Gamma lines out of selected library assigned to cursor position

16. Info buttons and info display – nuclide list • List of nuclides and gamma lines present in selected library: • Isotope name and half life • Gamma lines assigned • Gamma line decay probability in percent

17. Info buttons and info display – peak report • Click on ‘peak report’ and ‘peak search’ button • Info display shows details of detected peaks: • Gamma energy (keV) with Energy error • FWHM (keV) • Peak area with Area error and peak rating • Each peak which was detected by the peak search algorithm turns in the displayed spectrum from black to red

18. Info buttons and info display – nuclide report • Click on ‘nuclide report’ and ‘peak search’ button • Info display shows identified nuclides • Name of isotope with activity estimation • Amount of Peaks found in relation to peaks assigned to isotope • Quality factor of ID • Confidence level (certain, uncertain, very uncertain) • peaks not assigned to any isotope

19. Identified isotopes and their confirmation • Confirmation of isotopes by spectra simulation: • Select isotope from result list • double click on isotope’s name  spectra simulation with peak information • Spectra simulation (blue line) should have a good match with the gamma spectrum • Display of peak information content: • isotope name • Gamma energy position • Decay probability (if enabled)

20. Blue line: spectrum simulation red line: peaks found Gamma energies of the selected isotope

21. Evaluation of IdentiFINDER RID spectra • Convert IdentiFINDER Ultra spectrum (*spc) to ORTEC format (*.chn) • Start Identify and open *.chn file • Select a detector type • Nearest match for IdentiFINDER Ultra: NaI 1.5x1.5” • Select absorber(s), measurement distance • Select basic library IdentiFINDER • Select variation by temperature 1% • Evaluate spectrum by ‘peak search’ and ‘nuclide report’ • Simulate spectrum by double click on results (nuclides)

22. Evaluation of HPGe - MMCA based spectra • Record spectrum and save as ANSII *.spe file • Start Identify and open *.spe file • Select the detector type HPGe 500x15 • Select absorber(s), measurement distance • Select basic library IdentiFINDER to get first overview • Select variation by temperature 0.2% • Evaluate spectrum by ‘peak search’ and ‘nuclide report’ • Simulate spectrum by double click on results (nuclides) • Repeat evaluation with: ‘Standard-HPGe-MEST’ and ‘single isotope’ library

23. Evaluation of HPGe micro-detective spectra • Convert micro-detective spectrum (*.spc) to ORTEC format (*.chn) • Start Identify and open *.chn file • Select the detector type HPGe GEM15 • Select absorber(s), measurement distance • Select basic library IdentiFINDER to get first overview • Select variation by temperature 0.2% • Evaluate spectrum by ‘peak search’ and ‘nuclide report’ • Simulate spectrum by double click on results (nuclides) • Repeat measurement with: ‘Standard-HPGe-MEST’ and ‘single isotope’ library

24. Evaluation of AT6101 backpack spectra • AT6101 records spectra in *.spe format • Start Identify and open *.spe file • Select a detector type • Nearest match for the backpack is : NaI 3x3” • Select absorber(s), measurement distance • Select basic library IdentiFINDER • Select variation by temperature 1% • Evaluate spectrum by ‘peak search’ and ‘nuclide report’ • Simulate spectrum by double click on results (nuclides)

25. How to deal with peaks not identified? • ID complete if all gamma peaks in the spectrum are assigned to isotopes • Unknown peaks could be caused by: • Another unknown source • Peaks from daughter products • Single and double escape peaks, or coincident effects • Long measurement times, which records: • Peaks with low decay probability • Background (K-40, Ra-226 and Th232 with daughters) • Solution: • Add isotopes to library and try to evaluate the peak by ‘cursor info’ • Use extra tools: nuclide navigator, nuclide 2000, gamma spectra catalogues, spectra simulations (nucleonica)