CHM14 Neutron Detector

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Mark Rowley
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CHM14 Neutron Detector

Post by Mark Rowley » Wed Jun 26, 2019 8:29 pm

Running some preliminary tests using a Ludlum 2221 scaler and a boron CHM14 neutron detector.

My neutron source is a 10 month old Po210 Nuclispot paired up with Be. It’s far from its original potency but it still gives me some output I can use for testing.

The moderator is a 10x8” cylinder of paraffin wax.

With no moderator or source nearby, the CHM14 will average around 1cpm. With the source and tube in the moderator cavity I average approx 15cpm. As a side note, my neutron count numbers were almost double 10 months ago when the Nuclespot was new.

The tube is blind to all the Ra226 gamma sources I have on hand. I’ll conduct the same test with xrays from the fusor later this evening.

Mark Rowley
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Last edited by Mark Rowley on Thu Jun 27, 2019 4:49 am, edited 1 time in total.

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Richard Hull
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Re: CHM14 Neutron Detector

Post by Richard Hull » Thu Jun 27, 2019 4:37 am

Sounds good to me. You seem to have the bias setup right. Oddly I was working with my NIM neutron system today. I had to add two quarts of water to the moderator. (evaporation) I flipped out as it seemed to read only about 1/2 what it should until I checked the moderator and saw it was only half full. All O.K. now.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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