Cube fusor build

For posts specifically relating to fusor design, construction, and operation.
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Frank Sanns
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Re: Cube fusor build

Post by Frank Sanns » Sat Jan 04, 2020 2:25 am

Great work again Jon! Nice to see your latest evolution. My comments that follow are not a critique of your work but rather a quest for answers.

More and more of these anisotropy conclusions seem to be coming up. I am still skeptical of the conclusion because I have yet to see the separation between direction and location of neutron output.

Consider a black box cube. You cannot see in and you have no idea what is going on inside. You take a neutron measurement and find that neutron count is higher when you measure or activated at one of the faces. Does this imply that neutrons are directional or that they are being formed closer to the face? Any one experiment cannot distinguish. A minimum of two and preferably at least three measurements must be made to identify what is occurring.

Measurements can be done with coincidence counting, directional arrays, activation arrays, non directional sensor arrays to name a few.

One technique that I have used time and time again is the inverse square relationship. This occurred to me one day that Carl Willis and I were U ore prospecting. There was much radioactive sand in the area so there were many hot spots that we had to dig. Thinking that there must be a better way, I started taking measurements at various heights above the soil level. The inverse square law must be in effect so I took a reading then raised the probe until only one quarter the number of counts were seen. This distance then would be how far the source must have been from my probe. Of course this excludes the shielding effects of the ground but you get the idea. Found some great ore specimens those days with minimal wasted digging for diffuse radioactive sand.

The point is that the inverse square law is a powerful tool to not only see directionality but distance to the source. In the case of Jon's cube, a measurement or activation at 90 degrees to the suspected spot of neutron formation would be necessary to prove location of formation. Then backing off the two measuring or activation devices by double the distance should give one quarter the neutron numbers of both. If not, then the neutrons are indeed coming off in a shower in one direction over another.

I would really like to see this one resolved as it is an important result. I personally do not believe that the neutrons are coming of directionally but rather are being formed in a region that is deceptively giving higher neutron counts only because of closer proximity to the measuring device.

I may move this post to another forum so I do not contaminate Jon's excellent work but I feel it is relevant in this thread for the discussions already occurring.

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Mark Rowley
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Re: Cube fusor build

Post by Mark Rowley » Sat Jan 04, 2020 3:01 am

Amazing work Jon. I may end up trying the cylindrical grid as well after a couple other mods are put in place.

Mark Rowley

Jon Rosenstiel
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Re: Cube fusor build

Post by Jon Rosenstiel » Tue Jan 07, 2020 4:20 pm

Frank, great idea that may help us get to the bottom of this conundrum, much appreciated. I’ve worked on this just enough to realize that the detector clamped in a lab stand is not going to cut it, takes too long to reposition the detector and is not very accurate. I’m in the process of upgrading my setup, but the bronchitis I contracted over the holidays isn’t helping one bit.

Jon R

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