Deceleration of ion and plasma flows in Hall-effect electrostatic systems

Abstract

The paper presents the results of a theoretical and experimental study of the deceleration of ion and plasma flows in ion decelerators operating on the basis of an E→×B→ discharge with the Hall effect. For quantitative computational analysis of the deceleration process, an analytical model of the electric deceleration layer (E-layer) is proposed; it is based on a diffusion model of a discharge with closed electron drift, in the approximation of classical electron mobility transverse to the magnetic field, taking into account the electron current escape out of the ion beam region. Estimated dependences of the E-layer parameters and the efficiency of ion kinetic energy conversion into electrical energy on the parameters of the incident ion flow are given. The experimental results on the deceleration of plasma and ion flows with the xenon ion energy from 0.15 to 2 keV and ion current density in the range of 1–30 A/m2 are presented. The E-layer properties such as its thickness, the efficiency of the ion kinetic energy conversion into electrical energy, and the layer position in the deceleration channel were determined by test. We studied the effect of partial closure of the electron drift current in the deceleration channel outside the plasma flow volume on the efficiency of energy conversion. The study results can be used to build a detailed phenomenological pattern of plasma flow deceleration in devices with an E→×B → discharge with the Hall effect and to assess the possibility of developing various ion decelerators.