Thermal synchrotron radiation from RRMHD simulations of the double tearing mode reconnection - Application to the Crab flares

TL;DR

This paper uses resistive relativistic MHD simulations to explore how the double tearing mode in current sheets can produce synchrotron radiation, explaining Crab nebula flares.

Contribution

It demonstrates that the double tearing mode in striped pulsar wind regions can account for observed gamma-ray flares in the Crab nebula.

Findings

Crab GeV flares can be explained by DTM in striped wind with high magnetization.

Simulations reproduce explosive reconnection phases leading to synchrotron emission.

Guide field presence influences the tearing instability dynamics.

Abstract

We study the magneto-hydrodynamic tearing instability occurring in a double current sheet configuration when a guide field is present. This is investigated by means of resistive relativistic magneto-hydrodynamic (RRMHD) simulations. Following the dynamics of the double tearing mode (DTM), we are able to compute synthetic synchrotron spectra in the explosive reconnection phase. The pulsar striped wind model represents a site where such current sheets are formed, including a guide field. The variability of the Crab nebula/pulsar system, seen as flares, can be therefore naturally explained by the DTM explosive phase in the striped wind. Our results indicate that the Crab GeV flare can be explained by the double tearing mode in the striped wind region if the magnetization parameter $\sigma$ is around $10^5$.