Semianalytical treatment of current density of particles injected by a monoenergetic source

TL;DR

This paper develops a semianalytical model for calculating current density of particles injected by a monoenergetic source, incorporating time dependence and velocity diffusion, applicable to multi-ion plasmas, and clarifies previous discrepancies in analytical formulas.

Contribution

It introduces a comprehensive semianalytical approach that accounts for time dependence and velocity diffusion in current density calculations, enhancing the physical understanding of neutral beam injection.

Findings

Provides exact solutions that clarify discrepancies in earlier formulas.

Enhances physical understanding of current drive mechanisms.

Applicable to multi-ion-species plasma environments.

Abstract

This paper extends the semianalytical treatment of fast ion current density to take into account time dependence and velocity diffusion using solutions of Boltzmann equation with a complete Coulomb collision term (Goncharov et al. 2010 Phys. Plasmas 17 112313). An arbitrary angle distribution of the fast ion source is assumed. The results are applicable to multi-ion-species plasma. Since analytical results provide an extra physical insight and constitute a reliable basis for verification of numerical codes, it is desirable to obtain exact solutions where possible. New results clarify the discrepancies between analytical formulae in earlier bibliography and improve the physical basis of neutral beam injection current drive.