Double-diffusive processes in stellar astrophysics

TL;DR

This paper reviews the recent developments in understanding double-diffusive processes in stellar astrophysics, emphasizing their implications for stellar evolution and summarizing key theoretical results for an astrophysical audience.

Contribution

It provides clear derivations of important double-diffusive phenomena and discusses their impact on stellar evolution, updating the field as of early 2019.

Findings

Summarizes recent advances in double-diffusive convection in stars.

Highlights implications for stellar evolution and observations.

Connects theoretical results with astrophysical applications.

Abstract

The past 20 years have witnessed a renewal of interest in the subject of double-diffusive processes in astrophysics, and their impact on stellar evolution. This lecture aims to summarize the state of the field as of early 2019, although the reader should bear in mind that it is rapidly evolving. An Annual Review of Fluid Mechanics article entitled "Double-diffusive convection at low Prandtl number" (Garaud, 2018) contains a reasonably comprehensive review of the topic, up to the summer of 2017. I focus here on presenting what I hope are clear derivations of some of the most important results with an astrophysical audience in mind, and discuss their implications for stellar evolution, both in an observational context, and in relation to previous work on the subject.