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arXiv · 1907.13312

Possible indications for jittering jets in core collapse supernova explosion simulations

Abstract

I analyse recent three-dimensional hydrodynamical simulations of exploding core collapse supernovae (CCSNe) and find that a rapid increase in the diagnostic explosion energy occurs parallel to, or very shortly after, the accretion of gas with relatively large amount of angular momentum and/or specific angular momentum. The tendency towards a positive correlation between angular momentum accretion and the increase in the explosion energy appears despite the absence of magnetic fields in the simulations. I speculate that the inclusion of magnetic fields would make this positive correlation much stronger and would increase the explosion energy. At times, the high angular momentum accretion leads to a bipolar outflow that in some cases changes directions. I argue that there is a mutual influence between neutrino heating and stochastic angular momentum, and that both operate together to explode the star with bipolar outflows that change directions, namely, jittering jets. This study calls for a deep flow analysis of simulations of CCSNe, e.g., to present the flow structure, the density, and the angular momentum of the flow near the newly born neutron star (NS).

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Noam Soker. 2019-07-31. Possible indications for jittering jets in core collapse supernova explosion simulations. https://arxiv.org/abs/1907.13312

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