Fast magnetization of a high-to-low-beta plasma beam

Abstract

Industrially acceptable methods of plasma ion implantadn not only require an efficient means of switching the negative highvoltage pu1ses.l but also require an energy efficient plasma generation system. To do this, a non-magnetized microwave generated plasma was designed and is being built. Pictured below is the block diagram. The power source is from a Model PPS-2.5 AS ,2500-W. 2.45 GHz Varian (Eimac) microwave power pack with a WR-340 waveguide port. Both the forward and reflected power is measured with a Model EW3-DPM3S Varian power meter. A Model EW3-HH Varian HH tuner (power matching device) is included for impedance matching. Next, a Model GS315 Gerling RMS step transistion. which steps WR-340 (S band) waveguide to WR-284 waveguide, is included since there are many more microwave components available in the WR-284 size. Next, a standard EH tuner is included which is used for most of the matching since the plasma is a changing load. Then. an isolator is included to

Conditions for plasmoid penetration across abrupt magnetic barriers

“…This is something that is known to happen to plasmoids in the transition region [e.g., Song et al (1990) (Ref. 10)] and which has no counterpart in our simplified (symmetric) magnetic diffusion calculation.…”

“…They correspond to magnetic expulsions in the range from ⌬B / B = 13% to ⌬B / B = 74%. Finally, there are the experiments by Song et al 10 In these experiments, measurements were made several meters from a high ␤ k plasma source, after a phase of beam expansion, and of magnetic diffusion into the plasma. The situation close to the plasma source, immediately after entering the transverse field, is the one relevant for the plot of Fig.…”

“…6 and 7) that for narrow plasmoids, self-polarization can occur up to at least ␤ k = 300, while for wide plasmoids, magnetic expulsion has been reported down to ␤ k = 1.3. 10 One of the purposes of the present work is to resolve this issue.…”

Jets Downstream of Collisionless Shocks

“…Rather, the plasmoids penetrated the strong magnetic field region by magnetic expulsion, where the kinetic energy density of the plasmoid was enough to displace the magnetic field lines as it penetrates (Song et al 1990;. Finally, in some experiments the plasmoids were not able to penetrate into the strong magnetic field region (Song et al 1990;, referred to as rejection.…”

Propagation of neutralized plasma beams

“…Recent experiments, using intense ion beams and plasma gun beams demonstrate that fast magnetization can be accounted for by simply including classical-Hall effects. 1,2 Hall effects do not dissipate energy, yet can act as a vorticitydriven source of magnetic field that greatly increases the plasma-magnetization rate.…”