The growth of helium burning cores

Abstract

Helium burning in the convective cores of horizontal branch and `red clump' stars appears to involve a process of `ingestion' of unburnt helium into the core, the physics of which has not been identified yet. I show here that a limiting factor controlling the growth is the buoyancy of helium entering the denser C+O core. It yields a growth rate which scales directly with the convective luminosity of the core, and agrees with constraints on core size from current asteroseismology.

Accepted for publication in A&A

References in corpus (3)

• Beyond Mixing-length Theory: a step toward 321D
• Uncertainties on near-core mixing in red-clump stars: effects on the period spacing and on the luminosity of the AGB bump
• On the proper use of the Schwarzschild and Ledoux criteria in stellar evolution computations

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