title: Mixed Pierce-two-stream instability development in an extraction system of a negative ion source.
abstract: Mixed Pierce-two-stream instability may occur in an extraction system of a negative ion source based on a volume-produced plasma. The reasons for instability development are discussed. Analytically the conditions of unstable beam propagation are determined. The instability threshold is shown to be increased compared with the pure Pierce instability. The influence of inclined perturbations on the instability behavior is investigated. The numerical calculations are performed in COMSOL Multiphysics. The simulation results confirm the existence of such a mixed instability appearance that develops due to both the electrons of the external circuit and the background positive ions.
authors.affiliation: National Research Nuclear University MEPhI, Kashirskoye sh. 31, Moscow 115409, Russian Federation.
authors.forename: H Y
authors.initials: HY
authors.lastname: Barminova
authors.affiliation: State Scientific Center "All-Russian Electrotechnical Institute (VEI)," Krasnokazarmennaya St. 12, Moscow 111250, Russian Federation.
authors.forename: A S
authors.initials: AS
authors.lastname: Chikhachev