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arXiv · 1209.3173

Charged current neutrino interactions in core-collapse supernovae in a virial expansion

C. J. Horowitz·G. Shen·Evan O'Connor·Christian Ott
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Abstract

Core-collapse supernovae may depend sensitively on charged current neutrino interactions in warm, low density neutron rich matter. A proton in neutron rich matter is more tightly bound than is a neutron. This energy shift \Delta U increases the electron energy in \nu_e + n --> p + e, increasing the available phase space and absorption cross section. Likewise \Delta U decreases the positron energy in \bar \nu_e + p --> n + e^+, decreasing the phase space and cross section. We have calculated \Delta U using a model independent virial expansion and we find \Delta U is much larger, at low densities, than the predictions of many mean field models. Therefore \Delta U could have a significant impact on charged current neutrino interactions in supernovae. Preliminary simulations of the accretion phase of core-collapse supernovae find that \Delta U increases \bar \nu_e energies and decreases the \nu_e luminosity.

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C. J. Horowitz, G. Shen, Evan O'Connor, Christian Ott. 2012-09-14. Charged current neutrino interactions in core-collapse supernovae in a virial expansion. https://doi.org/10.1103/physrevc.86.065806

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