Unveiling stellar (and planetary) internal dynamics with the fully compressible MUSIC code

TL;DR

This paper introduces the MUSIC code, a fully compressible hydrodynamical simulation tool designed to overcome limitations of traditional anelastic codes, enabling detailed study of stellar interior dynamics including convection and wave phenomena.

Contribution

The MUSIC code provides a novel, fully compressible approach that improves modeling of stellar hydrodynamics beyond the anelastic approximation used in prior codes.

Findings

Enhanced simulation of stellar convection and boundary mixing.

Better modeling of internal waves in stars.

Overcoming time step constraints of explicit integration.

Abstract

Multidimensional hydrodynamical simulations have transformed the study of stellar interiors over the past few decades. Most codes developed during that time use the anelastic approximation, which fixes the thermal structure of simulations and filters out sound waves. Many of them also use explicit time integration, which imposes severe constraints on the time step of the simulations. In this context, MUSIC is developed to overcome these limitations. Its main scientific objective is to improve the phenomenological approaches used in 1D stellar evolution codes to describe major hydrodynamical and MHD processes. Here, we review recent applications of the MUSIC code, that focus mainly on convection, convective boundary mixing and waves in stars that possess convective cores, shells and/or envelopes.