Search found 30 matches

by Steve Dubyk
09 Dec 2016, 16:01
Forum: Spectrum
Topic: Pb-210 Spectrum
Replies: 0
Views: 1229

Pb-210 Spectrum

I researched this spectrum for another forum but thought you might be interested. I had never heard of Pb-210 (radiolead) as a source, so it was initially a little challenging. Rather a little project, but still pretty cool!

Best Regards,

Steve
by Steve Dubyk
13 Oct 2016, 08:55
Forum: Introductions
Topic: Peter new here
Replies: 12
Views: 4169

Re: Peter new here

Peter, the most common layered lead castles consist of lead, then lead-free pewter, and copper on the inside. I cannot help you with the optimum thickness of each. My constraints for a lead castle are weight (since I move mine around) and cost - both pewter and copper sheeting is a little expensive....
by Steve Dubyk
12 Oct 2016, 13:19
Forum: Introductions
Topic: Peter new here
Replies: 12
Views: 4169

Re: Peter new here

Peter, the shielding sounds good. If you look at the sample gamma spectra on Steven's web site, and a couple that I have attached, your spectrum looks good. However, I do not know the cause of the peaks below 300 keV. If you Google K-40 gamma spectrum and look at the pictures, they all look similar....
by Steve Dubyk
10 Oct 2016, 13:59
Forum: Introductions
Topic: Peter new here
Replies: 12
Views: 4169

Re: Peter new here

Peter, welcome to the forum! What type of shielding are you using for your detector for measurement? It appears that the low end gamma may be due to background rad.

Steve
by Steve Dubyk
18 Sep 2016, 09:58
Forum: Spectrum
Topic: Thorite versus Uranothorite
Replies: 0
Views: 1010

Thorite versus Uranothorite

A friend gave me a little crystal labeled thorite a few days ago, and since we have been identifying thorite at a few of the mines in the Petaca district here in NM, I figured to include a spectra of it for the record. Well, it did not look like thorite from the spectra! I compared the spectra to a ...
by Steve Dubyk
23 Feb 2016, 14:47
Forum: Resources
Topic: Efficiency Calculations for Selected Scintillators
Replies: 1
Views: 2874

Efficiency Calculations for Selected Scintillators

Attached is a very handy document provided by Saint-Gobain that answers many questions about the efficiency of a variety of scintillation materials. Topics covered include detector counting efficiency, photopeak efficiency, and gamma and x-ray absorption efficiency of different scintillators.
by Steve Dubyk
21 Feb 2016, 02:32
Forum: Spectrum
Topic: Lanthanum gamma spectrum
Replies: 2
Views: 2621

Re: Lanthanum gamma spectrum

Lodovico, that is really a nice spectrum and set up. How long did it take you to acquire it? I used a 40x40 mm probe with 100g of the metal, and it took about 5 hours! I was originally under the impression that the only impurity in lanthanum was Ac-227 and it's daughters, but it does look like the T...
by Steve Dubyk
09 Aug 2015, 04:32
Forum: Spectrum
Topic: Photo peak duplication when the source is on the side of the scintillator
Replies: 11
Views: 4383

Re: Photo peak duplication when the source is on the side of the scintillator

Hello folks! This is a topic in the "sad but true" category. I have attached graphs from the defective crystals I have encountered over the years, including one featuring the double peak. What is most unfortunate is that the sealed probe here was the first one I used for gamma spec, and spent many m...
by Steve Dubyk
24 Jun 2015, 13:36
Forum: Spectrum
Topic: W-187 Spectrum with FWT Rainbow
Replies: 3
Views: 2192

Re: W-187 Spectrum with FWT Rainbow

Interesting spectrum....how pure is the tungsten sample? There is a Fe-59 peak at 192 keV, could the sample be ferro tungsten? Ferro tungsten is a common commodity.

Steve Dubyk
by Steve Dubyk
22 Jun 2015, 09:36
Forum: Spectrum
Topic: Pa-234 and -234m Specrtra
Replies: 2
Views: 1920

Re: Pa-234 and -234m Specrtra

Pieter, thank you for noticing that, I did also. The Theremino program uses a recursive deconvolution algorithm and I suspect that is the reason for the unusually sharp peak at 1001 keV and also the noise. Additionally, I reduced the peak equalizers in the program for all energy levels other than th...