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arXiv · 1010.3376

Old White Dwarf Stars with Some Hydrogen -- Cooling Curves

Eugene Y. Chen·Brad M. S. Hansen
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Abstract

We present theoretical analysis on old white dwarf stars with \emph{some} hydrogen, that possess a mass of surface hydrogen from $1\times10^{-11}M_{\sun}$ to $1\times10^{-7}M_{\sun}$. The evolution of such objects is complicated by convective mixing from surface convection zone to the underlying helium layer. In this paper, we provide first self-consistent, quantitative investigation on the subject of convective mixing. Numerical cooling curves and chemical evolution curves are obtained as a function of white dwarf mass and hydrogen content. Such results will be applied to the investigation of the non-DA gap of \citet{1997ApJS..108..339B} in a later paper.

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Eugene Y. Chen, Brad M. S. Hansen. 2010-10-16. Old White Dwarf Stars with Some Hydrogen -- Cooling Curves. https://arxiv.org/abs/1010.3376

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