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arXiv · 0805.3752

Influence of light nuclei on neutrino-driven supernova outflows

A. Arcones·G. Martinez-Pinedo·E. O'Connor·A. Schwenk·H. -Th. Janka·C. J. Horowitz·K. Langanke
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Abstract

We study the composition of the outer layers of a protoneutron star and show that light nuclei are present in substantial amounts. The composition is dominated by nucleons, deuterons, tritons and alpha particles; 3He is present in smaller amounts. This composition can be studied in laboratory experiments with new neutron-rich radioactive beams that can reproduce similar densities and temperatures. After including the corresponding neutrino interactions, we demonstrate that light nuclei have a small impact on the average energy of the emitted electron neutrinos, but are significant for the average energy of antineutrinos. During the early post-explosion phase, the average energy of electron antineutrinos is slightly increased, while at later times during the protoneutron star cooling it is reduced by about 1 MeV. The consequences of these changes for nucleosynthesis in neutrino-driven supernova outflows are discussed.

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A. Arcones, G. Martinez-Pinedo, E. O'Connor, A. Schwenk, H. -Th. Janka, C. J. Horowitz, K. Langanke. 2008-05-25. Influence of light nuclei on neutrino-driven supernova outflows. https://doi.org/10.1103/physrevc.78.015806

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