Help a newbie out?

[Chase]

Hello everyone!

I'm just collecting my first spectrums in quite a while. The last time I did this was in college and we had to do everything manually (including using a physical book of radionuclides and energy peaks to identify stuff). So, with this new world of technology, surely there are better ways to do things. Does anyone know of a good database with energy peak lookups or something of the sorts that can help identify radionuclides or x-ray peaks?

Also, using PRA, does anyone know how to increase the maximum energy that it can bin? I'm sure it is something obvious but I just can't seem to find the right setting and I'm capped at 2200 keV. Fine for most things but there are a few peaks I might want higher for.

Thanks in advance!

[Rob Tayloe]

With respect to using PRA with Steven's MCA device, there are some videos that Steven made a little while back. I found these quite useful. In an earlier thread Steven also discusses setting up PRA. Links follow -

viewtopic.php?f=7&t=995

Link to excellent videos below -
https://www.gammaspectacular.com/blue/v ... w-to-setup or directly from YouTube

https://www.youtube.com/watch?v=OuZN4CPdQhk

https://www.youtube.com/watch?v=uFZ8zWYdCQU

https://www.youtube.com/watch?v=_VtMjrrrd64

[Sesselmann]

Chase,

The dynamic range of a soundcard microphone input is around -1.2 to +1.2 volts and PRA, Becqmoni and IMPULSE divide this range into +- 100 arbitrary units (arb.u).

Typically we adjust the gain so you can catch everything from 0 to 3000 keV as this covers the range of naturally ocurring isotopes, but if you want to catch high energy cosmic rays or anything like that you can just lower your gain so it fits into the range.

On the other hand if your question is the more trivial one where stuff just ends up outside your screen, then it's the Up and Down buttons on your keyboard that function as Zoom keys.

I strongly recommend learning the PRA keyboard shortcuts from the last mage in the manual, it reduces a lot of head scratching 😉

Merry Christmas, Marrakesh mass, or Just Grease On seatings 🎄

[ColoRad-o]

It's hard to overstate how useful InterSpec (https://sandialabs.github.io/InterSpec/) can be for this. Once you have a reasonably calibrated spectrum from PRA you can look up plausible peaks in any particular energy window. You can re-calibrate if you wish, or fit your data to a quadratic or cubic. Click on a peak and you can do a nuclide search based on likelihood ('profile'), energy difference, branching ratios, etc. It will also allow you to identify a main peak and its Compton features, identify sum peaks, even escape peaks. There is a host of other tools, including decay info: you specify the isotopes, ages, and time spans and it will produce alpha, beta, and gamma rates over time, exportable to CSV files for external analysis. You can export a hi-rez PNG file with your peak labels indicating what you measured, what's in the database, and which isotope.

[Chase]

You've got me sold on InterSpec, this is really cool. I'll have to play around with it a bit longer but here is a spectrum from my thoriated lens! I really like the nuclide lookup feature, that is handy!

[ColoRad-o]

Beautiful spectrum!

[jneilson]

Does anyone know of a good database with energy peak lookups or something of the sorts that can help identify radionuclides or x-ray peaks?

There's a few good tools for this.

Spectrum analysis software often has library-based peak identification tools, and while it's best to use a simplified library based on what you expect in your sample for actual analysis, there's often also default wide ranging libraries with most things you're ever likely to see that can be good for identifying unknown peaks - e.g. Suspect.lib in Ortec packages and I forget the name but I think something like Lib0.NLB in Canberra/Mirion Genie.
Watch out though as library-based ID can be tripped up by common interferences (eg U-235/Ra-226 @ 186keV; Bi-214/Eu-152 @ 1408keV; Bi-214/Ta-182/Sc-46 @ 1120keV, Cs-137/Ag-110m @ 657-661keV ). It's also often based on older nuclear data and there may be mistakes and inaccuracies in the libraries.

If it doesn't match based on my software's peak ID; or I'm concerned about possible interferences and misidentifications, my go-to tool is the IAEA Isotope Browser app. https://play.google.com/store/apps/deta ... s.nuclides
It's got great features to lookup decay data for any nuclide, either by typing in or finding on the Chart of Nuclides. If you've got a peak to ID; toggle to Expert mode and enter a range of energies (and select gamma as the radiation type), and it will list everything that falls in that range. (It can also be worth filtering by half-life so you don't get flooded with things that decay in seconds and you never see).

Otherwise, I go to the source nuclear data. One of the most trusted is the Decay Data Evaluation Project (DDEP) http://www.lnhb.fr/home/nuclear-data/nu ... ata-table/ This is based on evaluations of the experimental data, so is generally very accurate - but if you've got something a little more unusual, it doesn't have all the nuclides.

For that reason, I generally use NUDAT3 data
https://www.nndc.bnl.gov/nudat3/

There's also plenty of other places I've used before:

• JANIS: https://www.oecd-nea.org/janisweb/index.html
• ENDF: https://www-nds.iaea.org/exfor/endf.htm
• IAEA Live Chart of Nuclides: https://www-nds.iaea.org/relnsd/vcharth ... tHTML.html
• JEFF: https://www.oecd-nea.org/dbdata/jeff/
• Gamma Energies table: https://web.physics.indiana.edu/courses ... _table.pdf
• List of common gamma energies: [broken link removed - Steven]
• Appendix D of Gordon Gilmore's Practical Gamma Ray Spectroscopy
• FENDL: https://www-nds.iaea.org/fendl20/fen-decay.htm
• JENDL: https://wwwndc.jaea.go.jp/nucldata/index.html
• FISPACT decay data: https://fispact.ukaea.uk/nuclear-data/downloads/
• Lund/LBNL: http://nucleardata.nuclear.lu.se/toi/