Proton-temperature-anisotropy-driven magnetic fields in plasmas with cold and relativistically hot electrons

Abstract

AbstractWe present a dispersion relation for a plane-polarized electromagnetic wave in plasmas composed of cold electrons, relativistically hot electrons and bi-Maxwellian protons. It is shown that the free energy in proton-temperature anisotropy drives purely growing electromagnetic modes in our three-component plasma. Expressions for the growth rates and thresholds of instabilities are presented. The present results are relevant for explaining the origin of spontaneously generated magnetic fields in laboratory and astrophysical plasmas.