The VIPER Conductivity Model
Abstract
Beam propagation codes such as the hose simulation code VIPER require simple models for treating the generation of conductivity by the bean pulse. The VIPER conductivity model calculates the electron density n sub e (r,zeta,z) where zeta = ct-z is the distance from the beam head. The rate equation for n sub e treaties beam impact ionization, avalanche ionization, and recombination. Rate coefficients and momentum transfer frequency are functions of the electron temperature T sub e which is itself estimated from the ratio of the local electric field to the neutral gas density. Since VIPER treats both monopole and dipole beam dynamics, the perturbed or dipole conductivity must also be calculated. Benchmark comparisons between the VIPER model and more elaborate treatments of beam-generated conductivity are also presented. Keywords: Air chemistry; Beam propagation; Charge particle beam; Beam generated ionization; Beam generated conductivity; Intense relativistic electron beam.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 24, 1986
- Accession Number
- ADA167134
Entities
People
- R. F. Hubbard
- S. P. Slinker
Organizations
- United States Naval Research Laboratory