Simulation of an expanding plasma using the Boris algorithm

POSTER

Abstract

We present a Boris algorithm simulation in a cylindrical geometry of charged particle motion in a helicon plasma confined by a diverging magnetic field. Laboratory measurements of ion velocity distribution functions (ivdfs) provide evidence for acceleration of ions into the divergent field region in the center of the discharge. The increase in ion velocity is inconsistent with expectations for simple magnetic moment conservation given the magnetic field mirror ratio and is therefore attributed to the presence of a double layer in the literature. Using measured electric fields and ivdfs (at different radial locations across the entire plasma column) upstream and downstream of the divergent magnetic field region, we compare predictions for the downstream ivdfs to measurements. We also present predictions for the evolution of the electron velocity distribution function downstream of the divergent magnetic field.

Authors

  • Luke Neal

    West Virginia University, Department of Physics, West Virginia University, Department of Physics and Astronomy, Department of Physics and Astronomy, West Virginia University

  • Evan Aguirre

    West Virginia University, Department of Physics and Astronomy, Department of Physics and Astronomy, West Virginia University, West Virginia University

  • Thomas Steinberger

    West Virginia University, Department of Physics and Astronomy, Department of Physics and Astronomy, West Virginia University, West Virginia University

  • Timothy Good

    Gettysburg College, Department of Physics, Department of Physics, Gettysburg College, Gettysburg College

  • Earl Scime

    West Virginia University, West Virginia Univ, West Virginia University, Department of Physics, West Virginia University, Department of Physics and Astronomy, Department of Physics and Astronomy, West Virginia University