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arXiv · 2206.00011

An Atlas of Convection in Main-Sequence Stars

Adam S. Jermyn·Evan H. Anders·Daniel Lecoanet·Matteo Cantiello
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Abstract

Convection is ubiquitous in stars and occurs under many different conditions. Here we explore convection in main-sequence stars through two lenses: dimensionless parameters arising from stellar structure and parameters which emerge from the application of mixing length theory. We first define each quantity in terms familiar both to the 1D stellar evolution community and the hydrodynamics community. We then explore the variation of these quantities across different convection zones, different masses, and different stages of main-sequence evolution. We find immense diversity across stellar convection zones. Convection occurs in thin shells, deep envelopes, and nearly-spherical cores; it can be efficient of inefficient, rotationally constrained or not, transsonic or deeply subsonic. This atlas serves as a guide for future theoretical and observational investigations by indicating which regimes of convection are active in a given star, and by describing appropriate model assumptions for numerical simulations.

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Adam S. Jermyn, Evan H. Anders, Daniel Lecoanet, Matteo Cantiello. 2022-05-31. An Atlas of Convection in Main-Sequence Stars. https://doi.org/10.3847/1538-4365%2Fac7cee

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