Predictive fluid model for self-consistent description of inductive RF coupling in powerful negative hydrogen ion sources

Abstract RF-driven negative hydrogen ion sources are typically operated at low frequencies around 1 MHz, gas pressures or below Pa and large power densities up to 10 Wcm -3 . Owing these conditions as well the current discharge geometries antenna layouts, RF coupling is far from optimized, i.e. only a fraction η of delivered by generator absorbed plasma. This considerably limits performance reliability sources. To study bidirectional self-consistent fluid model introduced. Taking into account interplay between nonlinear Lorentz force electron viscosity (usually neglected in state-of-the-art models) steady state solution obtained, where trends reflect experimental data. Solutions calculated but with increased masses indicate that latter responsible for systematically η, which observed experimentally when deuterium instead used feed gas.