Calming Plasma's Stormy Seas

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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rcain
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Joined: Mon Apr 14, 2008 2:43 pm
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Re: Calming Plasma's Stormy Seas

Post by rcain »

fascinating and inportant result: fast ion streams/injections reduce ion-thermal-gradient instabilities (ITG) - good post!

D Tibbets
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Joined: Thu Jun 26, 2008 6:52 am

Re: Calming Plasma's Stormy Seas

Post by D Tibbets »

Suprathermal ions, what are those? It sounds like they are referring to ions at higher energies than the Maxwell Botzman distribution, but that would invalidate this well accepted distribution. Perhaps they mean the few ions at the extreme upper limit the thermalized plasma having disproportionate effect on the plasma behavior (from a stability standpoint), relative to simple summation of their energy and numbers with current (past?) modeling assumptions. Another disproportionate effect sort of applies to the fusion rate due to the fusion cross section at different temps, and I am assuming they are implying some other disproportionate effect for these high energy ions (but still within the MB distribution) for the mentioned instability. The dance between theory and experiment continues.

An alternate possibility (pure speculation) might be that some of the ions in the injection beams may initially be at substantial increased energies. Perhaps due to resonate effects with the microwave heatine beams, etc.

If there is a subset of extra thermal or suprathermal ions that persist long enough to alter this instability, it begs the question of the effect of fusion ions in the overall thermal plasma. Will they have a beneficial (?) effect on the plasma stability. In the Tokamak these fusion (ignition- heating) ions thermalize with the rest of the plasma, possibly boosting the percentage of the high thermal tail (altering the shape of the thermalized temperature curve) if thermalization does not quite reach the fully thermalized picture. Is this useful? Is it possible the high fusion output of JET showed this? Did they have the instermentation to measure it?

Things are much simplier in the Polywell, or are they...

Dan Tibbets
To error is human... and I'm very human.

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