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arXiv · astro-ph/0207595

Onset of Convectionon a Pre-Runaway White Dwarf

L. J. Dursi·A. C. Calder·A. Alexakis·J. W. Truran·R. Rosner·M. Zingale·B. Fryxell·P. M. Ricker·F. X. Timmes·K. Olson
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Abstract

Observed novae abundances and explosion energies estimated from observations indicate that there must be significant mixing of the heavier material of the white dwarf (C+O) into the lighter accreted material (H+He). Accordingly, nova models must incorporate a mechanism that will dredge up the heavier white dwarf material, and fluid motions from an early convection phase is one proposed mechanism. We present results from two-dimensional simulations of classical nova precursor models that demonstrate the beginning of a convective phase during the `simmering' of a Nova precursor. We use a new hydrostatic equilibrium hydrodynamics module recently developed for the adaptive-mesh code FLASH. The two-dimensional models are based on the one-dimensional models of Ami Glasner, and were evolved with FLASH from a pre-convective state to the onset of convection.

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L. J. Dursi, A. C. Calder, A. Alexakis, J. W. Truran, R. Rosner, M. Zingale, B. Fryxell, P. M. Ricker, F. X. Timmes, K. Olson. 2002-07-26. Onset of Convectionon a Pre-Runaway White Dwarf. https://doi.org/10.1063/1.1518191

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