Pair-Instability Supernovae of Non-Zero Metallicity Stars

TL;DR

This study presents 2D simulations of pair-instability supernovae in non-zero metallicity stars, showing minimal mixing due to stellar winds stripping the hydrogen envelope, which affects the explosion's observational features.

Contribution

First 2D simulations of pair-instability supernovae in stars with non-zero metallicity, highlighting the impact of stellar winds on explosion dynamics and mixing.

Findings

Minimal mixing occurs during the explosion.

Stellar winds strip the hydrogen envelope before supernova.

Weak mixing from nuclear burning does not alter observational signatures.

Abstract

Observational evidence suggests that some very massive stars in the local Universe may die as pair-instability supernovae. We present 2D simulations of the pair-instability supernova of a non-zero metallicity star. We find that very little mixing occurs in this explosion because metals in the stellar envelope drive strong winds that strip the hydrogen envelope from the star prior to death. Consequently, a reverse shock cannot form and trigger fluid instabilities during the supernova. Only weak mixing driven by nuclear burning occurs in the earliest stages of the supernova, and it is too weak to affect the observational signatures of the explosion.