MHD Simulations of Core Collapse Supernovae with Cosmos++

TL;DR

This study uses 2D MHD simulations with Cosmos++ to investigate the growth of MRI in core-collapse supernovae, revealing how magnetic and rotational dynamics influence supernova evolution.

Contribution

It demonstrates the application of high-resolution remapping techniques in 2D MHD simulations to study MRI growth in supernovae, confirming previous findings with improved resolution.

Findings

MRI appears near the equator during collapse

Higher resolution enhances overturns and transport

Results agree with earlier studies by Akiyama et al. and Obergaulinger et al.

Abstract

We performed 2D, axisymmetric, MHD simulations with Cosmos++ in order to examine the growth of the magnetorotational instability (MRI) in core--collapse supernovae. We have initialized a non--rotating 15 solar mass progenitor, infused with differential rotation and poloidal magnetic fields. The collapse of the iron core is simulated with the Shen EOS, and the parametric Ye and entropy evolution. The wavelength of the unstable mode in the post--collapse environment is expected to be only ~ 200 m. In order to achieve the fine spatial resolution requirement, we employed remapping technique after the iron core has collapsed and bounced. The MRI unstable region appears near the equator and angular momentum and entropy are transported outward. Higher resolution remap run display more vigorous overturns and stronger transport of angular momentum and entropy. Our results are in agreement with the earlier work by Akiyama et al. (2003) and Obergaulinger et al. (2009).