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arXiv · 0709.0417

Nucleosynthesis in the Early Galaxy

F. Montes·T. C. Beers·J. Cowan·T. Elliot·K. Farouqi·R. Gallino·M. Heil·K. -L. Kratz·B. Pfeiffer·M. Pignatari·H. Schatz
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Abstract

Recent observations of r-process-enriched metal-poor star abundances reveal a non-uniform abundance pattern for elements $Z\leq47$. Based on non-correlation trends between elemental abundances as a function of Eu-richness in a large sample of metal-poor stars, it is shown that the mixing of a consistent and robust light element primary process (LEPP) and the r-process pattern found in r-II metal-poor stars explains such apparent non-uniformity. Furthermore, we derive the abundance pattern of the LEPP from observation and show that it is consistent with a missing component in the solar abundances when using a recent s-process model. As the astrophysical site of the LEPP is not known, we explore the possibility of a neutron capture process within a site-independent approach. It is suggested that scenarios with neutron densities $n_{n}\leq10^{13}$ $cm^{-3}$ or in the range $n_{n}\geq10^{24}$ $cm^{-3}$ best explain the observations.

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F. Montes, T. C. Beers, J. Cowan, T. Elliot, K. Farouqi, R. Gallino, M. Heil, K. -L. Kratz, B. Pfeiffer, M. Pignatari, H. Schatz. 2007-09-04. Nucleosynthesis in the Early Galaxy. https://doi.org/10.1086/523084

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