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arXiv · 1411.3266

Neutrino-pair bremsstrahlung from nucleon-$α$ versus nucleon-nucleon scattering

Rishi Sharma·Sonia Bacca·Achim Schwenk
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Abstract

We study the impact of the nucleon-$α$ P-wave resonances on neutrino-pair bremsstrahlung. Because of the non-central spin-orbit interaction, these resonances lead to an enhanced contribution to the nucleon spin structure factor for temperatures $T \lesssim 4$ MeV. If the $α$-particle fraction is significant and the temperature is in this range, this contribution is competitive with neutron-neutron bremsstrahlung. This may be relevant for neutrino production in core-collapse supernovae or other dense astrophysical environments. Similar enhancements are expected for resonant non-central nucleon-nucleus interactions.

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Rishi Sharma, Sonia Bacca, Achim Schwenk. 2014-11-12. Neutrino-pair bremsstrahlung from nucleon-$α$ versus nucleon-nucleon scattering. https://doi.org/10.1103/physrevc.91.042801

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