Just found this link by MSimon on Talk-Polywell:
http://wwwppd.nrl.navy.mil/nrlformulary/
The NRL Plasma Formulary has been the mini-Bible of plasma physicists for the past 25 years. It is an eclectic compilation of mathematical and scientific formulas, and contains physical parameters pertinent to a variety of plasma regimes, ranging from laboratory devices to astrophysical objects.
Just download the PDF or PS. That gives you some plasma background (some mathematics and physics required).
What it also shows on page 41, is that a Focus is roughly superior to Z-Pinches, Laser Plasma, and other Fusion Experiments, in respect of density and temperature. Well, it doesn’t show anything about confinement time…
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