Non-helical Dynamo Mechanisms in an Accretion Disk

Non-helical Dynamo Mechanisms

Astrophysical systems such as accretion disks around black holes are able to sustain magnetic fields on timescales much longer than the resistive decay timescale. Dynamo theory describes how these magnetic fields are maintained. Although mean-field dynamo theory is well-developed in systems with a density gradient, the driving mechanisms in systems that lack such a gradient are still under debate. I explore two possible mechanisms, the magnetic shear-current effect and the stochastic-alpha effect, and their connection to dynamo transport coefficients.

This research was one of the topics during my Fulbright fellowship. It was presented at the 2018 EPS meeting (proceedings). Note the typo in the second sentence (the MRI transports angular momentum outward).