Chaos and Turbulent Nucleosynthesis Prior to a Supernova Explosion

TL;DR

This paper discusses advanced 3D simulations of turbulent stellar flows before supernova, revealing chaotic dynamics and offering new insights into pre-supernova processes and mixing mechanisms.

Contribution

It introduces high-resolution 3D turbulent simulations of late stellar evolution, showing chaotic flow behavior and aligning theoretical models with numerical results.

Findings

Simulations show highly turbulent, chaotic flow in pre-supernova stars.

Theoretical models are consistent with numerical turbulence results.

New dynamic picture of presupernova stages emerges.

Abstract

Three-dimensional (3D), time dependent numerical simulations, of flow of matter in stars, now have sufficient resolution to be fully turbulent. The late stages of the evolution of massive stars, leading up to core collapse to a neutron star (or black hole), and often to supernova explosion and nucleosynthesis, are strongly convective because of vigorous neutrino cooling and nuclear heating. Unlike models based on current stellar evolutionary practice, these simulations show a chaotic dynamics characteristic of highly turbulent flow. Theoretical analysis of this flow, both in the Reynolds-averaged Navier-Stokes (RANS) framework and by simple dynamic models, show an encouraging consistency with the numerical results. It may now be possible to develop physically realistic and robust procedures for convection and mixing which (unlike 3D numerical simulation) may be applied throughout the long life times of stars. In addition, a new picture of the presupernova stages is emerging which is more dynamic and interesting (i.e., predictive of new and newly observed phenomena) than our previous one.