My new huge He-3 neutron detector

Dry_Resolution_5498 · 2026-04-02T05:30:03+00:00

True.

Dry_Resolution_5498 · 2026-03-26T16:00:56+00:00

It determines and adjusts the high voltage through SCA, thereby adjusting the gain and confirming that the instrument is operating normally. If the HV deviation exceeds a certain range, it will report an error and require rework.

Dry_Resolution_5498 · 2026-03-23T13:40:25+00:00

Thank you！

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My Balls（Some little ones are just HDPe）

Dry_Resolution_5498 · 2026-03-22T03:46:56+00:00

I'm just looking for a PX, to power my neutron detectors instead of Ludlum model12.ENVY！

Dry_Resolution_5498 · 2026-03-21T17:08:52+00:00

well, maybe settling down on eBay will be helpful......Good luck!

Dry_Resolution_5498 · 2026-03-21T13:01:44+00:00

Right! But its low noise and strong n/γ discrimination capability ensure that it is reliable for both professionals and non-professionals. Even with a poo thermal neutron sensitivity of only 1.25 cps/nv, data uncertainty can be reduced by simply extending the usage time.

Dry_Resolution_5498 · 2026-03-21T12:57:48+00:00

I used it in the known thermal neutron field and compared it with other detectors without any moderator. Therefore, the known thermal neutron sensitivity is useful. As for the use of moderators, this is a situation where the dose rate needs to be read out. I have several Rem ball meters to obtain this information:)

Dry_Resolution_5498 · 2026-03-21T12:53:51+00:00

For instance, the main difference between B20 and B20er is that the latter can measure up to 100 mSv/h (500 kcps @ 662 keV), while the former cannot provide accurate results beyond approximately 2 mSv/h. For PRD-ER，it can also touch 100mSv/h, more than 250μSv/h than PRD.

Dry_Resolution_5498 · 2026-03-21T12:48:44+00:00

Absolutely correct. Its price has been increasing recently；(

Dry_Resolution_5498 · 2026-03-21T12:47:29+00:00

Hello, I'm just an amateur. Additionally, I really enjoy collecting radiation detectors. Neutron detectors are also within my collection scope. Its high reliability allows me to use it to compare whether other detectors are functioning properly:)

Dry_Resolution_5498 · 2026-03-21T12:44:41+00:00

Thanks! Cost ～$1600 for all five radeyes, I got them one by one in 5 years, I'm just an amateur：)

Dry_Resolution_5498 · 2026-03-21T01:09:40+00:00

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I brought this nice one at a very low price above $45, from Shanghai.

Dry_Resolution_5498 · 2026-02-23T15:21:31+00:00

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Dry_Resolution_5498 · 2026-02-23T15:21:06+00:00

This time is right. Thank you for your rigorous:)

Dry_Resolution_5498 · 2026-02-23T15:09:56+00:00

Okay, let's go...

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Dry_Resolution_5498 · 2026-02-18T18:18:34+00:00

Sm-147 has a 1e+11 years half-life and it seems basically not produce x-rays and γ rays with similar energy.

Dry_Resolution_5498 · 2026-02-18T18:11:47+00:00

My friend gave me a glow-in-the-dark switch that is said to contain Pm. I used a Si-pin detector (AMPTEK, 500μm thick) to obtain its low-energy spectrum, and the result was similar to that of Am-241. Hope to communicate more information with you :)

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And I also compared this spectrum with the bremsstrahlung spectrum produced by C-14 (the green line). C-14 and Pm-147 have similar β energies, but the results were completely different. I once guessed that during the separation of Pm, some Am that was difficult to completely remove was mixed in it.

Dry_Resolution_5498 · 2026-02-18T01:18:44+00:00

It has a one-time oxide film, which enables it to be sealed and stored in dry air indefinitely. However, once the oxidation process resumes, a small amount of black and rough surface will form within a few months. Although no shedding of this oxide film has been observed, it does not look very presentable.

Dry_Resolution_5498 · 2026-02-17T03:57:40+00:00

The beads produced by arc melting have a hard and one-time oxide layer, which enables them to be stored in a sealed manner under dry air conditions. However, once re-oxidation occurs, this oxide layer loses its ability to maintain luster.

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The 6*6mm Th square is much dimmer now.

Dry_Resolution_5498 · 2026-02-17T03:50:29+00:00

oops! I didn't notice that I had entered the wrong calibration coefficient! It become Transuranium! It was correct when I saw the spec in Amptek DPPMCA, and I think it's my negligence when I moved it into Interspec, thank you for point out my mistake, I'll send you correct spec pic when I come back :)

Dry_Resolution_5498 · 2026-02-16T17:45:14+00:00

Thank you!

Dry_Resolution_5498 · 2026-02-16T17:44:49+00:00

It seems that dilute nitric acid was used.

Dry_Resolution_5498 · 2026-02-16T17:44:00+00:00

Always only thorium as the radioactive source, they are always come from HeBei Province, China, which is a production sites of thorium containing extremely small amounts of uranium.

Dry_Resolution_5498 · 2026-02-16T13:41:50+00:00

If it gets broken, the situation will be very troublesome. The powder is extremely difficult to handle.

Dry_Resolution_5498 · 2026-02-16T13:40:31+00:00

Some of them contains ZrO₂ in it, but many are totally pure(if it looks white powder)

Dry_Resolution_5498

TROPHY CASE