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arXiv · 1906.08787

Temporal and Angular Variations of 3D Core-Collapse Supernova Emissions and their Physical Correlations

Abstract

We provide the time series and angular distributions of the neutrino and gravitational-wave emissions of eleven state-of-the-art three-dimensional non-rotating core-collapse supernova models and explore correlations between these signatures and the real-time dynamics of the shock and the proto-neutron-star core. The neutrino emissions are roughly isotropic on average, with instantaneous excursions about the mean inferred luminosity of as much as $\pm$20%. The deviation from isotropy is least for the "$\nu_{\mu}$"-type neutrinos and the lowest-mass progenitors. Instantaneous temporal luminosity variations along a given direction for exploding models average $\sim$2$-$4%, but can be as high as $\sim$10%. For non-exploding models, they can achieve $\sim$25%. The temporal variations in the neutrino emissions correlate with the temporal and angular variations in the mass accretion rate. We witness the LESA phenomenon in all our models and find that the vector direction of the LESA dipole and that of the inner Y$_\mathrm{e}$ distribution are highly correlated. For our entire set of 3D models, we find strong connections between the cumulative neutrino energy losses, the radius of the proto-neutron star, and the $f$-mode frequency of the gravitational wave emissions. When physically normalized, the progenitor-to-progenitor variation in any of these quantities is no more than $\sim$10%. Moreover, the reduced $f$-mode frequency is independent of time after bounce to better than $\sim$10%. Therefore, simultaneous measurement of gravitational waves and neutrinos from a given supernova event can be used synergistically to extract real physical quantities of the supernova core.

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David Vartanyan, Adam Burrows, David Radice. 2019-06-20. Temporal and Angular Variations of 3D Core-Collapse Supernova Emissions and their Physical Correlations. https://doi.org/10.1093/mnras/stz2307

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