Search found 37 matches

by Sparky
26 Jun 2020, 08:00
Forum: Shielding
Topic: Modular Lead Shield for 2" detectors
Replies: 13
Views: 6818

Re: Modular Lead Shield for 2" detectors

Ciro, Thanks much for the correction. I understand. Internal to the detector, it would have to be an escape peak. Uranium 238 has a Th234 photopeak at 63.3 that might be a candidate, although the difference would be about 34 and this looks more like 30-32. It lines up at about the same energy as the...
by Sparky
24 Jun 2020, 08:06
Forum: Shielding
Topic: Modular Lead Shield for 2" detectors
Replies: 13
Views: 6818

Re: Modular Lead Shield for 2" detectors

I have seen a peak around 30 with all my Fiestaware and U glass spectrums and have racked my brain trying to figure out what it was. Now I know. Iodine x-rays.

Thanks!
by Sparky
22 Jun 2020, 13:00
Forum: Spectrum
Topic: A Tale of Triple Trinitite
Replies: 10
Views: 569

Re: A Tale of Triple Trinitite

Mike S. Got Plutonium? I have been interested in that peak near 40 for awhile. It is in Massimo's spectrums as well. The Pitteaurova paper (link and HPGe spectrum below) describes it as a combination of Sm K alpha1 x-rays (40.12 keV) and Plutonium 239 (38.7 keV). I think it lines up better at 39 tha...
by Sparky
21 Jun 2020, 02:46
Forum: General discussion
Topic: Instrument cables.
Replies: 6
Views: 210

Re: Instrument cables.

James,

I bought a couple of 1 m BNC X BNC cables from this ebay seller. I thought the quality and price was good.
He might be able to get different connections. Not sure.

324181797207
by Sparky
21 Jun 2020, 02:30
Forum: General discussion
Topic: Instrument cables.
Replies: 6
Views: 210

Re: Instrument cables.

Pavel, As you say, it depends on your set-up. I use the same type cable (#3 below) for my Ludlum survey meters and my Gamma Spectroscopy PMT adapters. I measured the capacitance of various cables and the results are listed below. Cable Capacitance tends to dampen the input signal. Whether it is an i...
by Sparky
17 Jun 2020, 12:58
Forum: Spectrum
Topic: Uranium Glass - Natural or Depleted Uranium?
Replies: 5
Views: 282

Re: Uranium Glass - Natural or Depleted Uranium?

I posted my spectrum on the GS iogroup and someone replied with this interesting link demonstrating how to make U-glass. I was surprised at how little U is required. I think my candleholder is similar in size and activity to the piece created here. https://www.youtube.com/watch?v=RGw6fXprV9U&feature...
by Sparky
14 Jun 2020, 02:00
Forum: The lounge
Topic: Fun thoughts about Ludlums.
Replies: 3
Views: 205

Re: Fun thoughts about Ludlums.

James, I think your taste is definitely for the fancier Models. I like the Model 2 because they can be obtained for very little money (often less than $100), but the front end is the same as the Model 3. The Model 2 has one less range setting than the Model 3, which reads up to 500,000 CPM. I have s...
by Sparky
10 Jun 2020, 03:26
Forum: Spectrum
Topic: Uranium Glass - Natural or Depleted Uranium?
Replies: 5
Views: 282

Re: Uranium Glass - Natural or Depleted Uranium?

Massimo, You've inspired me to check the one piece of Uranium Glass I own. It looks a lot like DU Fiestaware, except without the lead florescence. I was surprised it was DU, I thought it was older than that. In the USA, a lot of cheap colored glassware, including U-glass, was made in the 1930's and ...
by Sparky
28 May 2020, 11:50
Forum: Spectrum
Topic: Trinitite ā€“ The Quest for Europium and More: A 17 Day Gamma Spectrum
Replies: 22
Views: 2879

Re: Trinitite ā€“ The Quest for Europium and More: A 17 Day Gamma Spectrum

Massimo, We may never know for sure, but I believe the broad peak you identified at 80 keV, is most probably the various isotopes identified in the Pittauerova paper, including Ba133. Iā€™m no expert, but in my limited experience, lead florescence is a lopsided, elevated region between 75 keV (K alpha...
by Sparky
25 May 2020, 02:30
Forum: Spectrum
Topic: A Tale of Triple Trinitite
Replies: 10
Views: 569

Re: A Tale of Triple Trinitite

Mike,

What is nice about Trinitite is that it is so challenging you can revisit again and again as your hardware and technique improve.
FYI, if you haven't found it already, the Gamma Spectroscopy iogroup has a Files folder for Trinitite with a nice collection of technical papers.