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arXiv · 1608.05037

Impact of Nucleon-Nucleon Bremsstrahlung Rates Beyond One-Pion Exchange

Alexander Bartl·Robert Bollig·Hans-Thomas Janka·Achim Schwenk
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Abstract

Neutrino-pair production and annihilation through nucleon-nucleon bremsstrahlung is included in current supernova simulations by rates that are based on the one-pion-exchange approximation. Here we explore the consequences of bremsstrahlung rates based on a modern nuclear interactions for proto-neutron star cooling and the corresponding neutrino emission. We find that despite a reduction of the bremsstrahlung emission by a factor of 2-5 in the neutrinospheric region, models with the improved treatment exhibit only $\lesssim$5% changes of the neutrino luminosities and an increase of $\lesssim$0.7 MeV of the average energies of the radiated neutrino spectra, with the largest effects for the antineutrinos of all flavors and at late times. Overall, the proto-neutron star cooling evolution is slowed down modestly by $\lesssim$0.5-1 s.

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Alexander Bartl, Robert Bollig, Hans-Thomas Janka, Achim Schwenk. 2016-08-17. Impact of Nucleon-Nucleon Bremsstrahlung Rates Beyond One-Pion Exchange. https://doi.org/10.1103/physrevd.94.083009

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