Temperature-dependent Saturation of Weibel-type Instabilities in Counter-streaming Plasmas

Abstract

We present the first 2X2V continuum Vlasov–Maxwell simulations of interpenetrating, unmagnetized plasmas to study the competition between two-stream, Oblique, and filamentation modes in the weakly relativistic regime. We find that after nonlinear saturation of the fastest-growing two-stream and Oblique modes, the effective temperature anisotropy, which drives current filament formation via the secular Weibel instability, has a strong dependence on the internal temperature of the counter-streaming plasmas. The effective temperature anisotropy is significantly more reduced in colder than in hotter plasmas, leading to orders of magnitude lower magnetization for colder plasmas. A strong dependence of the energy conversion efficiency of Weibel-type instabilities on internal beam temperature has implications for determining their contribution to the observed magnetization of many astrophysical and laboratory plasmas.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 20, 2019
Source ID
10.3847/2041-8213/ab0556

Entities

People

  • Ammar Hakim
  • James Juno
  • Jason TenBarge
  • Valentin Skoutnev

Organizations

  • Air Force Office of Scientific Research
  • United States Department of Energy

Tags

Fields of Study

  • Physics

Readers

  • Plasma Physics / Magnetohydrodynamics
  • Thermal Physics or Thermal Science.

Technology Areas

  • Space
  • Space - Hall-Effect Thruster