Acceleration of Energetic Particles through Reconnection of Weakly Stochastic Magnetic Field

TL;DR

This paper investigates how magnetic reconnection in turbulent astrophysical environments accelerates energetic particles, providing evidence supporting a model where turbulence controls reconnection rates and results in efficient first-order Fermi acceleration.

Contribution

The study tests and confirms the Lazarian & Vishniac (1999) reconnection model in turbulent media and demonstrates first-order Fermi acceleration in reconnection regions.

Findings

Reconnection rate is governed by turbulence intensity and injection scale.

First-order Fermi acceleration occurs in turbulent reconnection volumes.

The model is applicable to various astrophysical reconnection events.

Abstract

Astrophysical media are turbulent and therefore reconnection should be treated in the presence of pre-existing turbulence. We consider the model of fast magnetic reconnection in Lazarian & Vishniac (1999) which predicts that the rate of reconnection is controlled by the intensity and the injection scale of turbulent motions. We provide new evidence of successful testing of the model and argue that the model presents a generic set up for astrophysical reconnection events. We study particle acceleration that takes place in volumes of driven turbulence as well turbulent volumes in the presence of large scale reconnection. We show that in the latter case the acceleration is of the first order Fermi type thus supporting the model of acceleration proposed in Gouveia dal Pino & Lazarian (2005).