Nonlinear Electromagnetic Waves in Magnetosphere of a Magnetar

TL;DR

This paper investigates nonlinear electromagnetic wave propagation in magnetar magnetospheres, modeling the environment as a QED vacuum and strongly magnetized plasma, revealing stable wave solutions that could influence energy transmission near pulsars.

Contribution

It introduces a nonperturbative method to analyze nonlinear wave effects in magnetar magnetospheres and discovers stable wave solutions that resist shock formation.

Findings

Identified a class of stable nonlinear wave solutions in a homogeneous plasma.

Showed that nonorthogonal components can prevent shock formation.

Potential implications for energy transfer processes near magnetars.

Abstract

We compute electromagnetic wave propagation through the magnetosphere of a magnetar. The magnetosphere is modeled as the QED vacuum and a cold, strongly magnetized plasma. The background field and electromagnetic waves are treated nonperturbatively and can be arbitrarily strong. This technique is particularly useful for examining non-linear effects in propagating waves. Waves travelling through such a medium typically form shocks; on the other hand we focus on the possible existence of waves that travel without evolving. Therefore, in order to examine the nonlinear effects, we make a travelling wave ansatz and numerically explore the resulting wave equations. We discover a class of solutions in a homogeneous plasma which are stabilized against forming shocks by exciting nonorthogonal components which exhibit strong nonlinear behaviour. These waves may be an important part of the energy transmission processes near pulsars and magnetars.