Simulations of the Magneto-rotational Instability in Core-Collapse Supernovae

TL;DR

This paper investigates the role of magneto-rotational instability (MRI) in core-collapse supernovae through analytical growth rate analysis and numerical simulations, revealing how differential rotation and stratification influence MRI behavior.

Contribution

It provides new insights into MRI growth, termination mechanisms, and long-term evolution in supernova environments, supported by both theoretical analysis and simulations.

Findings

MRI growth rates depend on rotation and stratification

Termination of MRI driven by parasitic instabilities

Long-term turbulent evolution characterized by specific scaling laws

Abstract

We assess the importance of the magneto-rotational instability in core-collapse supernovae by an analysis of the growth rates of unstable modes in typical post-collapse systems and by numerical simulations of simplified models. The interplay of differential rotation and thermal stratification defines different instability regimes which we confirm in our simulations. We investigate the termination of the growth of the MRI by parasitic instabilities, establish scaling laws characterising the termination amplitude, and study the long-term evolution of the saturated turbulent state.