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arXiv · 1007.1275

Production of Light Element Primary Process nuclei in neutrino-driven winds

A. Arcones·F. Montes
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Abstract

We present first comparisons between Light Element Primary Process (LEPP) abundances observed in some ultra metal poor (UMP) stars and nucleosynthesis calculations based on long-time hydrodynamical simulations of core-collapse supernovae and their neutrino-driven wind. UMP star observations indicate Z>38 elements include the contributions of at least two nucleosynthesis components: r-process nuclei that are synthesized by rapid neutron capture in a yet unknown site and LEPP elements (mainly Sr, Y, Zr). We show that neutrino-driven wind simulations can explain the observed LEPP pattern. We explore in detail the sensitivity of the calculated abundances to the electron fraction, which is a key nucleosynthesis parameter but poorly known due to uncertainties in neutrino interactions and transport. Our results show that the observed LEPP pattern can be reproduced in proton- and neutron-rich winds.

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A. Arcones, F. Montes. 2011-02-14. Production of Light Element Primary Process nuclei in neutrino-driven winds. https://doi.org/10.1088/0004-637x%2F731%2F1%2F5

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