Toroidal Self-Field Corrections to the Linear Dispersion Relation for the Negative Mass Instability in a Modified Betatron,
Abstract
Negative mass instability growth rates determined from three-dimensional pic code simulations of high current modified betatrons do not agree particularly well with available linear theory, as noted in a companion paper. Published linear analyses of the negative mass instability treat particle dynamics in toroidal geometry but the electromagnetic fields in cylindrical geometry. The authors have, therefore, developed a new model employing toroidal fields; it is valid or arbritary toroidal mode numbers and a variety of accelerator cavity minor cross sections. The beam minor radius is assumed small compared to that of the cavity. Derivation of the dispersion relation and numerical solutions of it will be presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1983
- Accession Number
- ADA135940
Entities
People
- B. B. Godfrey
- M. M. Campbell
- T. P. Hughes