Effect of the parameters of the plasma channel produced by a high-current relativistic electron beam in dense gaseous media on the beam transportation stability

Abstract

Results are presented from experimental studies of the time evolution of the plasma channel produced by a high-current electron beam (with an electron energy of Ee = 1.1 MeV, a beam current of Ib = 24 kA, and a pulse duration of t = 60 ns) in helium, nitrogen, neon, air, argon, krypton, xenon, and humid air (air: H2O) at pressures from 1 to 760 Torr. It is shown that, in gases characterized by a small ratio of the collision frequency to the gas ionization rate ui, the electron beam produces a broad high-conductivity plasma channel, such that Rb/Rp < 1, where Rb and Rp are the beam and channel radii, respectively. As a result, large-scale resistive hose instability is suppressed.