Yudai Suwa, Tomoya Takiwaki, Kei Kotake, Tobias Fischer, Matthias Liebendoerfer, Katsuhiko Sato
We present results from spherically symmetric (1D) and axially symmetric (2D) core-collapse supernova simulations. Our model is based on neutrino radiation hydrodynamics, including spectral neutrino transport. We apply the equations of state (EOS) from Lattimer & Swesty (LS) and Shen et al. (SHEN), and explore the differences obtained during the post-bounce phase prior to the possible onset of a neutrino-driven explosion. We confirm that in 1D simulations neutrino-driven explosions cannot be obtained for any of the employed EOS. In 2D, EOS induced structural differences lead to a more efficient neutrino heating, in particular for LS in comparison to the simulations that use SHEN. For simulations of the 15 M_sun progenitor with LS under investigation, it results in a continuous expansion of the stalled bounce shock to increasingly larger radii, which is absent using SHEN. Simulations of a 11.2 M_sun progenitor result in neutrino-driven explosions for all EOS under investigation, however slightly more powerful for LS than for SHEN and also slightly delayed for the latter. The generally more efficient neutrino heating using LS can be related to the higher electron antineutrino luminosity and the more mass enclosed inside the gain region. It also leads to the development of an aspherical downflow of material from large radii to the central protoneutron star surface for LS, which in turn supplies continuously energy to the protoneutron star. Moreover, we investigate several additional indicators of the explosion, e.g., the amplitude of the standing-accretion shock instability mode, the mass weighted average entropy in the gain region, the protoneutron star radius, the antesonic condition, and the ratio of advection and heating timescales.
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http://arxiv.org/abs/1206.6101
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