Momentum transport from current-driven reconnection in astrophysical disks

TL;DR

This paper explores how current-driven magnetic reconnection can facilitate angular momentum transport in astrophysical disks through theoretical and computational analysis of instabilities.

Contribution

It demonstrates that both resistive tearing and ideal instabilities can transport momentum in Keplerian flows, supported by nonlinear multiple mode computations.

Findings

Both resistive and ideal instabilities transport momentum.

Global Maxwell stress significantly contributes to momentum transfer.

Nonlinear simulations confirm the role of multiple modes.

Abstract

Current-driven reconnection is investigated as a possible mechanism for angular momentum transport in astrophysical disks. A theoretical and computational study of angular momentum transport from current-driven magnetohydrodynamic instabilities is performed. It is found that both a single resistive tearing instability and an ideal instability can transport momentum in the presence of azimuthal Keplerian flow. The structure of the Maxwell stress is examined for a single mode through analytic quasilinear theory and computation. Full nonlinear multiple mode computation shows that a global Maxwell stress causes significant momentum transport.