Particle-in-cell simulations of fast collisionless reconnection in gamma-ray burst outflows

TL;DR

This paper uses particle-in-cell simulations to study magnetic reconnection in gamma-ray burst outflows, revealing reduced efficiency due to electromagnetic fluctuations affecting reconnection dynamics.

Contribution

It introduces a simulation approach that includes full electromagnetic field dynamics, highlighting the impact of electric field fluctuations on reconnection efficiency in pair plasma jets.

Findings

Reconnection efficiency is reduced compared to previous models.

Electric field fluctuations hinder early x-point formation.

Electromagnetic fields are dynamically included in simulations.

Abstract

We present preliminary results of particle-in-cell simulations of collisionless magnetic reconnection for conditions that apply to magnetically dominated pair plasma jets such as those in gamma-ray bursts. We find similar behaviour to previous authors but with reduced reconnection efficiency. This results because we include the full electromagnetic field dynamically and allow electric field fluctuations to grow. Although weak, these fluctuations impede early x-point formation by periodically decelerating and even reversing the inflow.