First Neutrons (Unofficial)

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Conrad Farnsworth
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First Neutrons (Unofficial)

Post by Conrad Farnsworth » Fri Dec 02, 2011 6:54 am

I would like to "get my foot in the door" for first neutrons on 12-1-11. I will be posting more data soon and a video will also be uploaded (300mb and a bluetooth internet connection). Briefly, I am getting 100CPM 6" from the source minuscule compared to some of the great reactors, but, still neutrons, I am also running at ~30kv and my pressure varies from 10-30 microns the entire run, my I wasn't paying as much attention to the gauge as I was the clicking from the Ludlum model 12. My detector setup was a B-10 proportional tube next to a jug of mineral oil (added later in the video), and above ~1.5 inches of HDPE moderator. As you will see on the video to be linked, I do pull the tube away from the moderator and the counting stops, then bring it back in and the counting returns. Also, the chamber itself was shielding me from the xrays but a quick check with the handheld geiger counter at the viewport said the ground was getting a pretty nice dose of radiation. Like I said, you don't have to put me on the first neutron's list right now (if you decide to I would be thrilled), but I am convinced that once you see the video it should be pretty obvious I am getting neutrons.

Thanks for all of your help!

Sincerely,
Conrad Farnsworth

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Rich Feldman
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Re: First Neutrons (Unofficial)

Post by Rich Feldman » Fri Dec 02, 2011 7:34 am

Conrad Farnsworth wrote:
>> My detector setup was a B-10 proportional tube next to a jug of mineral oil (added later in the video), and above ~1.5 inches of HDPE moderator. As you will see on the video to be linked, I do pull the tube away from the moderator and the counting stops, then bring it back in and the counting returns. ...but I am convinced that once you see the video it should be pretty obvious I am getting neutrons.

Good work, Conrad.
Here's a trivial modification that could be instructional, and might strengthen your case for neutrons. Instead of pulling the detector tube away from the moderator (and changing its position or orientation with respect to your fusor):
Don't move the detector at all ! Just remove the moderator and see if the counting slows down significantly.
All models are wrong; some models are useful. -- George Box

Conrad Farnsworth
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Re: First Neutrons (Unofficial)

Post by Conrad Farnsworth » Fri Dec 02, 2011 8:19 am

Rich,

Thanks for the reply, the only problem I have with that is I built my PSU unit (cage) out of steel and used HDPE to insulate it. Another problem is that I didn't quite feel comfortable reaching that close to -30,000 volts. However, these next few runs I will play around with moderators and the placement of my B10 tube.

Thanks!

Conrad Farnsworth

P.S.

HERE IS THE LINK TO MY VIDEO http://www.youtube.com/watch?v=xk7w4J4uoXg

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Richard Hull
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Re: First Neutrons (Unofficial)

Post by Richard Hull » Fri Dec 02, 2011 3:43 pm

I am adding you to the neutron club! You had neutrons.

Rich Feldman was right; moving the tube means nothing at all. Inverse square law would nix that operation as any kind of proof.

What I saw, and was this was key, you had the fusor up, at voltage and as the gas went in you got counts with the plate PE moderator. But the final proof came when to inserted the mineral oil bottle. This was a superlative moderator and the counts really went up so obviously that only fast neutrons could be responsible.

Good proof, but not by moving the tube. It was all about inserting the mineral oil moderator. What bias voltage were you using on the B10? Just curious.

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.

RobertTubbs
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Re: First Neutrons (Unofficial)

Post by RobertTubbs » Fri Dec 02, 2011 6:17 pm

Richard, Conrad is still in high-school, I believe this qualifies him to be mentioned in the High School Achievers Section.

Congratulations Conrad, well done.

Now try to improve what you've got so far. A good start would be a valve that lets you valve off your fusor to leave it at partial vacuum, a full moderator, some new vacuum gauges and perhaps another stage or so on your multiplier. That aughta bump you along.

RT

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Adam Ingle
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Re: First Neutrons (Unofficial)

Post by Adam Ingle » Fri Dec 02, 2011 10:00 pm

Congrats, Conrad! Great video; hope to see more of your work in the future. Where did you end up coming across your B10 detector?

Conrad Farnsworth
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Re: First Neutrons (Unofficial)

Post by Conrad Farnsworth » Sat Dec 03, 2011 9:17 am

Richard,

My bias is 550 volts according to the analog gauge.

Adam,

I bought my B10 from Robert Tubbs.

Thank you all!

Conrad Farnsworth

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