Response of a Relativistically Streaming Pulsar Plasma

TL;DR

This paper develops a comprehensive theoretical framework for wave dispersion in pulsar plasmas, accounting for relativistic streaming, magnetic fields, and cyclotron resonances, with applications to Faraday rotation in pulsars and magnetars.

Contribution

It introduces a general response tensor for relativistically streaming pulsar plasma, including various relativistic and resonance effects, advancing the understanding of wave behavior in such extreme environments.

Findings

Derived a response tensor for relativistic pulsar plasma

Analyzed wave dispersion considering relativistic streaming and cyclotron resonances

Applied theory to explain generalized Faraday rotation in pulsars and magnetars

Abstract

The response tensor is derived for a relativistically streaming, strongly magnetized, one-dimensional J\"uttner distribution of electrons and positrons, referred to as a pulsar plasma. This is used to produce a general treatment of wave dispersion in a pulsar plasma. Specifically, relativistic streaming, the spread in Lorentz factors in a pulsar rest frame, and cyclotron resonances are taken into account. Approximations to the response tensor are derived by making approximations to relativistic plasma dispersion functions appearing in the general form of the response tensor. The cold-plasma limit, the highly relativistic limit, and limits related to cyclotron resonances are considered. The theory developed in this paper has applications to generalised Faraday rotation in pulsars and magnetars.