Stability of a Charged Particle Beam in a Resistive Plasma Channel

TL;DR

This paper investigates the stability of a relativistic charged particle beam in a resistive plasma channel with an external magnetic field, analyzing various unstable modes to understand beam filamentation and hose instability.

Contribution

It provides a comprehensive analysis of beam stability by deriving a dispersion relation that includes all azimuthal modes in a finite plasma channel.

Findings

Identification of multiple unstable modes causing beam filamentation.

Unified explanation of resistive hose instability and filamentation.

Dispersion relation encompassing all azimuthal modes.

Abstract

A self-focusing of a coasting relativistic beam in a plasma channel that is confined by an external magnetic field is studied as a means of reconditioning the beam emerging from a beam injector [a radio frequency quadrupole (RFQ)] for a linac. A detailed study of the beam stability in the self-focused beam has been carried out. In order to explain beam filaments and the resistive hose instability in a unified way, we treat all the azimuthal modes in the derivation of the dispersion relation in a finite plasma channel that exhibit many unstable modes, which are classified by Weinberg's scheme [Steven Weinberg, J. Math. 8, 614 (1967)].