Angular momentum fluctuations in the convective helium shell of massive stars

TL;DR

This study reveals significant angular momentum fluctuations in the convective helium shell of massive stars, which could influence supernova explosion mechanisms by aiding accretion disk and jet formation.

Contribution

It demonstrates that convective flows in evolved massive stars can generate large, fluctuating angular momentum, impacting core-collapse dynamics.

Findings

Angular momentum fluctuations are significant within the helium shell.

Convective flows can produce shells with net angular momentum in different directions.

Implications for supernova explosion mechanisms and star evolution.

Abstract

We find significant fluctuations of angular momentum within the convective helium shell of a pre-collapse massive star - a core-collapse supernova progenitor - which may facilitate the formation of accretion disks and jets that can explode the star. The convective flow in our model of an evolved M_ZAMS=15Msun star, computed with the sub-sonic hydrodynamic solver MAESTRO, contains entire shells with net angular momentum in different directions. This phenomenon may have important implications for the late evolutionary stages of massive stars, and for the dynamics of core-collapse.