Finally, just for Jon Rosenstiel, and thanks. B.O. T. fusion

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
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Richard Hull
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Finally, just for Jon Rosenstiel, and thanks. B.O. T. fusion

Post by Richard Hull »

Back in July 2021, Jon sent me a full fledged fast neutron detector he made up. It is basically a small light tight PMT with hornyak button scintillator. with two cables coming out of it. (one signal BNC, one SHV BNC)

His intent was for me to use it to scan around my fusor V which is, most probably, now, the only extant spherical fusor in normal operation on earth!
(might be wrong about that) the upshot is to see if the neutron levels might hint at beam on target boosted production of fusion even in a spherical system based on the grid structure beaming.

I finally got busy in implementing this concept and used the gift he sent to see for myself.

Within in the limits of my set up, which are many, I did see, in spite of my reservations a small increase in fusion around the 1-inch thick solid SS equatorial band CF flange region where the simple non-geodesic spherical grid beams were directed.

Now within the limits: The fusor has almost no free zones around its entire structure. due to two moderators, one large and one small along with wood walls and a thick wood base in very close quarters around it. All of these obstructions did not allow for what might be termed a clean sweep of the fusor body.

Now in spite of my reservations: The above materials all work to scatter neutrons via limited to complete thermalization of neutrons in and around the fusor. This could foul any precise reporting attempt.

Thus, I used the scintillator fast detector to scan about those few zones where the naked fusor body and flanges could be, in my opinion, resonable to not terribly affect the results of a quick hand held scan. Indeed, in spite of the horribly thick stainless steel flanges, the equatorial region of fusor V had about a 10% increase in counts where the beams might impact the walls. This was more or less verified as over only about 100 degrees of the "belly" band of the flange could be scanned. The grid throws out 6 radial beams in 60 degree impact points. I did note two general regions of the flange where more fast neutrons were detected. This militates for B.O.T. fusion at those points.

The above being said, fast neutrons were detected over what parts of the bare shell could be accessed as well!

That is my report and you may take it for what it is worth with all the provisos and cautions noted in the early part of this report.

Question? Why do I stick with the sphere?

1. It looks like a reactor vessel. - Silly, I know, however, it does not look like a part of the fusor plumbing. (cross, tee, or cylinder), the eyes go immediately to the strange sphere. All else in view are plumbing and attachments gathered about it.
2. It is large enough that just having a large box fan blow across it, suffices to cool it for the shorter limited runs I do here.

Thanks go to Jon for the gift and sorry it took so long to use it for why it was sent. Both Jon and my opinions were correct.
We seem to have learned that B.O.T. fusion is the main source of fusion in simple systems.

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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Jim Kovalchick
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Re: Finally, just for Jon Rosenstiel, and thanks. B.O. T. fusion

Post by Jim Kovalchick »

I agree with you that a spherical fusor looks like a fusor should. I have a beautiful, mostly spherical vessel that I thought a bit about going back to, but D usage and neutrons influence my decision.
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Richard Hull
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Re: Finally, just for Jon Rosenstiel, and thanks. B.O. T. fusion

Post by Richard Hull »

I do have a Gayo cube with mounted insulator in hand for over a year now, as noted in another post. I can only advance at my usual, single project pace which is typically slow. The HF, HV supply is currently at the fore.

In the cube image below, to the left of the cube is the gifted PMT/hornyak assembly that Jon sent to me which is the subject of the original post above.

Richard Hull
Attachments
Base Fusor VI Mod.jpg
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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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