Do I understand the theory behind the Fusor?

It may be difficult to separate "theory" from "application," but let''s see if this helps facilitate the discussion.
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John T K Sevdal
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Do I understand the theory behind the Fusor?

Post by John T K Sevdal » Fri May 23, 2014 1:40 pm

So far so good, been reading about Fusors for two days, and I feel I have a pretty good grasp of the concept now. But would like to know if I somehow misunderstood. So I will try to explain how I would explain it.
So what a Fusor basically does is to fuse two Deuterium atoms together into Helium. The Deuterium atom has one Neutron and one Proton. When fused together they produce an atom which has either two protons, forming Helium-3 and expelling a high energy Neutron. Or it will fuse into Tritium and expell a high energy Proton. The last fusion that can occur is into Helium-4 will will only generate gamma radiation. The last one being the rarest reaction, and the Helium-3 reaction being the most likely in our Fusor.
In order for the Fusion to happen there need to be applied energy into the reaction.
So as far as I understand there needs to be a negative voltage potential through the Cathode. So that electrons will flow from the ionized gas to the anode, while the nucleus is attracted to the Cathode because it has íts electrons stripped off. By having a very high voltage the Deuterium will become plasma, and it will be affected by electromagnetism because plasma has a charge.
The cathode is a sphere cage, the nucleus that hit the Cathode itself won't do anything, but the nucleus that are accelerated and miss the sphere cage will contuine into the center, where if another nucleus is present, it will fuse, and expell a high energy Neutron, which is the way to confirm if we have had Fusion happen. The cross section describes the likelyhood of nuclear interaction.
The reason we need vacuum is that we need to eliminate other particles, that won't react. So by having a very low pressure deuterium atmosphere inside, it will allow us to heat up the atoms with a less extreme amount of energy. The higher the pressure, the more atoms are present, and more energy would be required to achieve fusion.
Does this make any sense at all?
Thank you.

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Chris Bradley
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Re: Do I understand the theory behind the Fusor?

Post by Chris Bradley » Fri May 23, 2014 3:37 pm

In a broad-brush description, ignoring a few details, that's how it has been seen to work. But I don't think it does work like that.

So let me give you a slightly more generalised POV: You put a -ve cathode into an earthed shell and generate a glow discharge at vacuum pressures. If you reduce the pressure enough you can apply 20kV or more across the glow discharge, and so you get a mix of all sorts of particles with 20keV or more kinetic energy.

When deuterons with 20keV KE collide with each other, there is a probability they will fuse. So if you stick deuterium into that environment, accelerated deuterium has a chance to fuse.

Basically, you are generating an atomic soup where there is enough acceleration potential to get deuterons to fusible energies, and they might fuse if they bump into each other at those KEs.

Hope that helps!

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