Turbulent Magnetic Field Amplification from Spiral SASI Modes: Implications for Core-Collapse Supernovae and Proto-Neutron Star Magnetization

TL;DR

This study uses high-resolution simulations to show that SASI-driven turbulence in core-collapse supernovae can exponentially amplify magnetic fields to over 10^{14} G, even without rotation, impacting neutron star magnetization.

Contribution

It demonstrates that SASI-induced turbulence can significantly amplify magnetic fields in supernova environments, highlighting a mechanism for neutron star magnetization independent of progenitor rotation.

Findings

Magnetic fields grow exponentially due to SASI turbulence.

Final magnetic field strengths can exceed 10^{14} G.

Simulation resolution affects growth rate and magnitude estimates.

Abstract

We extend our investigation of magnetic field evolution in three-dimensional flows driven by the stationary accretion shock instability (SASI) with a suite of higher-resolution idealized models of the post-bounce core-collapse supernova environment. Our magnetohydrodynamic simulations vary in initial magnetic field strength, rotation rate, and grid resolution. Vigorous SASI-driven turbulence inside the shock amplifies magnetic fields exponentially; but while the amplified fields reduce the kinetic energy of small-scale flows, they do not seem to affect the global shock dynamics. The growth rate and final magnitude of the magnetic energy are very sensitive to grid resolution, and both are underestimated by the simulations. Nevertheless our simulations suggest that neutron star magnetic fields exceeding $10^{14}$ G can result from dynamics driven by the SASI, \emph{even for non-rotating progenitors}.