Efficient approximations of neutrino physics for three-dimensional simulations of stellar core collapse

M. Liebendoerfer; U. -L. Pen; C. Thompson

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Efficient approximations of neutrino physics for three-dimensional simulations of stellar core collapse

M. Liebendoerfer·U. -L. Pen·C. Thompson

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Abstract

Neutrino transport in spherically symmetric models of stellar core collapse and bounce has achieved a technically complete level, rewarded by the agreement among independent groups that a multi-dimensional treatment of the fluid-instabilities in the post-bounce phase is indispensable to model supernova explosions. While much effort is required to develop a reliable neutrino transport technique in axisymmetry, we explore neutrino physics approximations and parameterizations for an efficient three-dimensional simulation of the fluid-instabilities in the shock-heated matter that accumulates between the accretion shock and the protoneutron star. We demonstrate the reliability of a simple parameterization scheme in the collapse phase and extend our 3D magneto-hydrodynamical collapse simulations to a preliminary postbounce evolution. The growth of magnetic fields is investigated.

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M. Liebendoerfer, U. -L. Pen, C. Thompson. 2006-09-24. Efficient approximations of neutrino physics for three-dimensional simulations of stellar core collapse. https://arxiv.org/abs/astro-ph/0609651

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