Convective and non-convective mixing in AGB stars

Falk Herwig; Bernd Freytag; Tyler Fuchs; James P. Hansen; Robert M. Hueckstaedt; David H. Porter; Francis X. Timmes; Paul R. Woodward

arXiv · 0709.0197

Convective and non-convective mixing in AGB stars

Falk Herwig·Bernd Freytag·Tyler Fuchs·James P. Hansen·Robert M. Hueckstaedt·David H. Porter·Francis X. Timmes·Paul R. Woodward

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Abstract

We review the current state of modeling convective mixing in AGB stars. The focus is on results obtained through multi-dimensional hydrodynamic simulations of AGB convection, both in the envelope and the unstable He-shell. Using two different codes and a wide range of resolutions and modeling assumptions we find that mixing across convective boundaries is significant for He-shell flash convection. We present a preliminary quantitative analysis of this convectively induced extra mixing, based on a sub-set of our simulations. Other non-standard mixing will be discussed briefly.

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Falk Herwig, Bernd Freytag, Tyler Fuchs, James P. Hansen, Robert M. Hueckstaedt, David H. Porter, Francis X. Timmes, Paul R. Woodward. 2007-09-03. Convective and non-convective mixing in AGB stars. https://arxiv.org/abs/0709.0197

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