Search found 30 matches

by Steve Dubyk
22 Jun 2015, 04:04
Forum: Spectrum
Topic: Pa-234 and -234m Specrtra
Replies: 2
Views: 2395

Pa-234 and -234m Specrtra

Attached is a simple experiment to expose the weak and reclusive spectra from Pa-234 and Pa-234m, the later being a key indicator of the presence of U238.

Steve Dubyk
by Steve Dubyk
21 Jun 2015, 08:13
Forum: The lounge
Topic: I gave up a lifetime supply of neutrons.
Replies: 2
Views: 4931

Re: I gave up a lifetime supply of neutrons.

Geoff, that is truly a big decision, but I suspect you will enjoy your path forward. I have never regretted getting my degree in geology, even though at this point in my career I don't use it on the job much. I work and hike with other geologists, and our weekend fieldwork has been a real blast, int...
by Steve Dubyk
22 May 2015, 08:56
Forum: Spectrum
Topic: Fake Trinitite Spectrum
Replies: 7
Views: 8187

Re: Fake Trinitite Spectrum

I've attached a file with a few more examples of the trinitite spectrum, using different probes. I do like using trinitite for testing, especially to see the 26 and 59 keV from cesium and americium.

Steve
by Steve Dubyk
22 May 2015, 00:31
Forum: Resources
Topic: Indium 115 Spectrum - Gran Sasso Experiment
Replies: 1
Views: 4597

Indium 115 Spectrum - Gran Sasso Experiment

After reading what was necessary to detect the In-115 peak at 497 keV, looks like we won't see this one with our equipment! To us, it will be "observationally stable".
by Steve Dubyk
21 May 2015, 23:09
Forum: Resources
Topic: Trinitite Spectra - Various Authors
Replies: 0
Views: 3683

Trinitite Spectra - Various Authors

Here are three papers from different authors discussing trinitite and it's spectrum.

Steve Dubyk
by Steve Dubyk
21 May 2015, 23:00
Forum: Spectrum
Topic: Fake Trinitite Spectrum
Replies: 7
Views: 8187

Re: Fake Trinitite Spectrum

Ouch, it looks like typical U ore. Trinitite has dominant peaks from Cs-137 and Am-241, with lots of little peaks from Eu-152, -154, and other nuclides. I can post a couple of papers in the library that show the spectrum from trinitite.

Steve Dubyk
by Steve Dubyk
19 May 2015, 12:58
Forum: Spectrum
Topic: A Spectrum to Ponder
Replies: 12
Views: 6488

Re: A Spectrum to Ponder

The sample amount is critical. I initially used just a few grams, then went to about 30 grams, at which point I was able to collect a spectrum after about an hour, but it was weak. Keep in mind my largest detector is a 40x40 mm NaI. I then went to a 100 gram sample, since it was inexpensive. Suppose...
by Steve Dubyk
19 May 2015, 12:26
Forum: Resources
Topic: The Lanthanum 138 Spectrum
Replies: 0
Views: 3586

The Lanthanum 138 Spectrum

Interesting paper, especially for those using lanthanum halide detectors.

Steve Dubyk
by Steve Dubyk
19 May 2015, 12:13
Forum: Resources
Topic: Lutetium 176 Spectrum for Calibration
Replies: 0
Views: 3802

Lutetium 176 Spectrum for Calibration

Interesting paper.

Steve Dubyk
by Steve Dubyk
18 May 2015, 10:06
Forum: Spectrum
Topic: A Spectrum to Ponder
Replies: 12
Views: 6488

Re: A Spectrum to Ponder

Tom, you are correct, and that was fast! To obtain this spectrum you need a good size detector and sample, and a long run time, definitely the most challenging one I've done yet. I should mention that the peaks toward the lower end of the spectrum, below about 400 keV, are likely to be from Ac-227. ...