Radiative Signatures of Magnetic Reconnection: An Approach to Remote Probing of Reconnection Dynamics

TL;DR

This paper proposes a theoretical, data-driven method to identify and analyze radiation signatures of magnetic reconnection in astrophysical environments using spectral data and PIC simulations.

Contribution

It introduces a novel approach to remotely diagnose reconnection dynamics by linking spectral features to physical parameters through simulations and analytic calculations.

Findings

Spectral features can be connected to reconnection electric fields and magnetic parameters.

A method to estimate the ratio of reconnection electric field to plasmoid magnetic field from spectra.

Analytic formulas allow extraction of parameters like magnetic field and current sheet width in ultra-relativistic regimes.

Abstract

Magnetic reconnection drives a wide range of astrophysical phenomena, including geomagnetic storms, solar flares, and activity in blazars. However, direct measurement of key reconnection observables remains challenging due to the remote and extreme nature of these environments. While high-energy particle showers observed on Earth are often attributed to reconnection, the underlying mechanisms are not fully understood, and clear diagnostic signatures are lacking. We present a theoretical, data-driven approach for identifying reconnection radiation signatures and enabling remote diagnostics of reconnection in astrophysical settings through radiation spectra. Using particle-in-cell (PIC) simulations of magnetic reconnection, we generate radiation spectra and establish connections between spectral features and the underlying reconnection dynamics. We develop a method to estimate the ratio of the reconnection electric field to the plasmoid magnetic field from spectral data. Analytic calculations show that other parameters can be extracted in the ultra-relativistic reconnection regime, such as the magnetic field or the current sheet width.