Gamma Spectrometry Forum

WOW! And here all this time I thought the Gamma Spectacular was just a USB powered supply for varying the plate voltage on special one-tube (single valve) crystal radios that tune Exahertz instead of Kilohertz.

10 million pulse count each at 700v.

I obtained a sample of this from eBay user cgroat3573 and it took me some time to figure out the sources for the peaks. The peaks are around 33, 66, 96, 143.8, and 185.7. The 143.8, and 185.7 are from 235-U. In Logarithmic we also see the 766 and 1001 lines of 234m-Pa. Do I assume that the 96 peak i...

It's the blue one at the far left side. I've seen it before but didn't know what it was. So, I put the Americium sample in the castle and let it build up the peaks. Then I replaced the Americium with my Carnotite and watched its familiar peaks build. Then I used the known 59.5 and 609 peaks for cali...

To those interested,

Article on DIY $100 Muon dectector
http://www.symmetrymagazine.org/article ... n-detector

PDF available at https://arxiv.org/abs/1606.01196

Daryl

Here is my carnotite sample from Uravan, Montrose County, Colorado.

Looks the same except that 186KeV Radium peak is higher.

Running probe at 700v

Sample from Ralston Creek, Jefferson Co., Colorado.

ROI 47KeV 210-Pb, 100KeV 234-Pa, 186KeV 226-Ra, 238KeV 212-Pb, 295KeV 214-Pb, 352Kev 214-Pb, 609KeV 214-Bi and maybe 2204Kev 214-Bi.

Steven,

Thank you! Okay here is one at 700v where K40 sits around 79 arb.u.
If I go down to 650v, K40 will sit around the 34 arb.u mark.

BTW, is the above spectrum pretty much okay up to 700KeV?

Daryl

I wasn't seeing much on the higher end energies at 700v so I moved it up to 850v where I know where 59.5 is located on the scale. I found this to be quite a surprise! ROI from left to right - 63 & 93 from 234-Th, 186 from 226-Ra, 569 from 207-Bi (or 583 from 208-Th?), and 1001 from 234-Pa. Maybe...

Manuel,

My shielding is lead ingots and I get a little over a factor of 10 reduction of background.

Daryl