Similarites Between the Plasma Vortex Filaments (Relativistic and Nonrelativistic) Observed in the Plasma Focus and in Conventional Relativistic Electron-Beam Machines

In 1966, the Stevens Institute of Technology (SIT) plasma focus group demonstrated experimentally that the current sheath of the plasma focus is carried by pairs of plasma vortex filaments, which exhibit a force-free, Beltrami-type morphology. Experiments at SIT in 1980 and at the Air Force Weapons Laboratory (AFWL) show that relativistic electron beams traveling through a background gas of ∼1 Torr, and even in a “vacuum” diode, exhibit the same type of filamentary morphology, but on a spatial dimension scale, which extends down to the 1-µm region. Some of the experimental evidence accumulated in work at AFWL from 1979 to 1981, which supports the statement that there is a close similarity between current-carrying morphologies of the plasma focus and the relativistic beam machines, is presented.