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Refined numerical models for multidimensional Type Ia supernova simulations

M. Reinecke·W. Hillebrandt·J. C. Niemeyer
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Abstract

Following up on earlier work on this topic (Reinecke et al. 1999, A&A 347, pp. 724 and 739), we present an improved set of numerical models for simulations of white dwarfs exploding as Type Ia supernovae (SNe Ia). Two-dimensional simulations were used to test the reliability and numerical robustness of these algorithms; the results indicate that integral quantities like the total energy release are insensitive to changes of the grid resolution (above a certain threshold), which was not the case for our former code. The models were further enhanced to allow fully three-dimensional simulations of SNe Ia. A direct comparison of a 2D and a 3D calculation with identical initial conditions shows that the explosion is considerably more energetic in three dimensions; this is most likely caused by the assumption of axisymmetry in 2D, which inhibits the growth of flame instabilities in the azimuthal direction and thereby decreases the flame surface.

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M. Reinecke, W. Hillebrandt, J. C. Niemeyer. 2001-11-26. Refined numerical models for multidimensional Type Ia supernova simulations. https://doi.org/10.1051/0004-6361%3A20020323

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