
Accession Number : ADA111873
Title : Stability Properties of an Intense Relativistic Nonneutral Electron Ring in a Modified Betatron Accelerator.
Descriptive Note : Final rept.,
Corporate Author : NAVAL SURFACE WEAPONS CENTER SILVER SPRING MD
Personal Author(s) : Uhm,Hans S ; Davidson,Ronald C
PDF Url : ADA111873
Report Date : Sep 1981
Pagination or Media Count : 53
Abstract : Equilibrium and stability properties of an intense electron ring located at the midplane of an externally applied mirror field are investigated within the framework of the linearized VlasovMaxwell equations, including the important influence of equilibrium self fields and an applied field in the torodial direction. It is assumed that the ring is thin and that nu/gamma(sub b) 1, where nu is Budker's parameter and gamma(sub b)mcsquared is the characteristic electron energy. Equilibrium and stability properties are calculated for the choice of equilibrium distribution function in which all electrons have the same value of energy in a frame of reference rotating with angular velocity in the minor cross section of the ring, and a Lorentzian distribution in canonical angular momentum. Negativemass and resistancewall stability properties are calculated, and a closed dispersion relation is obtained for the case where the ring is located inside a toroidal conductor with finite resistivity and minor radius much less than the major radius. One of the most important features of the stability analysis is that the negativemass instability in a highcurrent ring can be stabilized by equilibrium selffield effects in circumstances where the self fields are sufficiently intense. Moreover, a modest spread Delta in canonical angular momentum can stabilize the resistivewall instability.
Descriptors : *Betatrons, *Electron beams, Stability, Relativity theory, Rings, Magnetic fields, Confinement(General), Cross sections, Angular momentum
Subject Categories : Particle Accelerators
Distribution Statement : APPROVED FOR PUBLIC RELEASE