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arXiv · 1809.00487

Repulsion of fallback matter due to central energy source in supernova

Toshikazu Shigeyama·Kazumi Kashiyama
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Abstract

The flow of fallback matter being shocked and repelled back by an energy deposition from a central object is discussed by using newly found self-similar solutions. We show that there exists a maximum mass accretion rate if the adiabatic index of the flow is less than or equal to 4/3. Otherwise we can find a solution with an arbitrarily large accretion rate by appropriately shrinking the energy deposition region. Applying the self-similar solution to supernova fallback, we discuss how the fate of newborn pulsars or magnetars depends on the fallback accretion and their spin-down power. Combining the condition for the fallback accretion to bury the surface magnetic field into the crust, we argue that supernova fallback with a rate of dM_{fb}/dt ~ 10^{-(4-6)} M_sun /s could be the main origin of the diversity of Galactic young neutron stars, i.e., rotation-powered pulsars, magnetars, and central compact objects.

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Toshikazu Shigeyama, Kazumi Kashiyama. 2018-09-05. Repulsion of fallback matter due to central energy source in supernova. https://doi.org/10.1093/pasj%2Fpsy108

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