MRI-driven angular momentum transport in protoplanetary disks

TL;DR

This paper reviews the role of MRI-driven turbulence in angular momentum transport within protoplanetary disks, discussing its implications for star and planet formation, and highlighting ongoing uncertainties and research directions.

Contribution

It provides a comprehensive overview of the historical development, current understanding, and open questions regarding MRI-driven turbulence in protoplanetary disks.

Findings

MRI-driven turbulence is a key mechanism for angular momentum transport.

Uncertainties remain about the saturation level of MRI turbulence.

Implications for planet formation models are still under investigation.

Abstract

Angular momentum transport in accretion disk has been the focus of intense research in theoretical astrophysics for many decades. In the past twenty years, MHD turbulence driven by the magnetorotational instability has emerged as an efficient mechanism to achieve that goal. Yet, many questions and uncertainties remain, among which the saturation level of the turbulence. The consequences of the magnetorotational instability for planet formation models are still being investigated. This lecture, given in September 2012 at the school "Role and mechanisms of angular momentum transport in the formation and early evolution of stars" in Aussois (France), aims at introducing the historical developments, current status and outstanding questions related to the magnetorotational instability that are currently at the forefront of academic research.