On The Development of Multidimensional Progenitor Models For Core-collapse Supernovae

TL;DR

This study develops multidimensional progenitor models for core-collapse supernovae, revealing significant aspherical perturbations that influence explosion mechanisms, with detailed analysis of convective properties in a 15 solar mass star across 1D, 2D, and 3D simulations.

Contribution

It presents the first comprehensive 3D pre-supernova models of a 15 solar mass star, highlighting the differences from 1D models and their implications for supernova explosion dynamics.

Findings

3D models show higher convective velocities than 1D models.

Large-scale convective power resides at spherical harmonic orders 2-4.

O-shell velocities in 3D are four times faster than in 1D models.

Abstract

Multidimensional hydrodynamic simulations of shell convection in massive stars suggest the development of aspherical perturbations that may be amplified during iron core-collapse. These perturbations have a crucial and qualitative impact on the delayed neutrino-driven core-collapse supernova explosion mechanism by increasing the total stress behind the stalled shock. In this paper, we investigate the properties of a 15 \msun model evolved in 1-,2-, and 3-dimensions (3D) for the final $\sim$424 seconds before gravitational instability and iron core-collapse using MESA and the FLASH simulation framework. We find that just before collapse, our initially perturbed fully 3D model reaches angle-averaged convective velocity magnitudes of $\approx$ 240-260 km s$^{-1}$ in the Si- and O-shell regions with a Mach number $\approx$ 0.06. We find the bulk of the power in the O-shell resides at large scales, characterized by spherical harmonic orders ($\ell$) of 2-4, while the Si-shell shows broad spectra on smaller scales of $\ell\approx30-40$. Both convective regions show an increase in power at $\ell=5$ near collapse. We show that the 1D \texttt{MESA} model agrees with the convective velocity profile and speeds of the Si-shell when compared to our highest resolution 3D model. However, in the O-shell region, we find that \texttt{MESA} predicts speeds approximately \emph{four} times slower than all of our 3D models suggest. All eight of the multi-dimensional stellar models considered in this work are publicly available.