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arXiv · 1904.01706

Weak Shock Propagation with Accretion. III. A Numerical Study On Shock Propagation & Stability

Stephen Ro·Eric R. Coughlin·Eliot Quataert
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Abstract

Core-collapse supernovae span a wide range of energies, from much less than to much greater than the binding energy of the progenitor star. As a result, the shock wave generated from a supernova explosion can have a wide range of Mach numbers. In this paper, we investigate the propagation of shocks with arbitrary initial strengths in polytropic stellar envelopes using a suite of spherically symmetric hydrodynamic simulations. We interpret these results using the three known self-similar solutions for this problem: the Sedov-Taylor blastwave describes an infinitely strong shock and the self-similar solutions from Coughlin et al. (2018b) (Paper I) and Coughlin et al. (2019) (Paper II) describe a weak and infinitely weak shock (the latter being a rarefaction wave). We find that shocks, no matter their initial strengths, evolve toward either the infinitely strong or infinitely weak self-similar solutions at sufficiently late times. For a given density profile, a single function characterizes the long-term evolution of a shock's radius and strength. However, shocks with strengths near the self-similar solution for a weak shock (from Paper I) evolve extremely slowly with time. Therefore, the self-similar solutions for infinitely strong and infinitely weak shocks are not likely to be realized in low-energy stellar explosions, which will instead retain memory of the shock strength initiated in the stellar interior.

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Stephen Ro, Eric R. Coughlin, Eliot Quataert. 2019-04-02. Weak Shock Propagation with Accretion. III. A Numerical Study On Shock Propagation & Stability. https://doi.org/10.3847/1538-4357/ab1ea2

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