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Short-lived p-nuclides in the early solar system and implications on the nucleosynthetic role of X-ray binaries

Nicolas Dauphas·Thomas Rauscher·Bernard Marty·Laurie Reisberg
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Abstract

The data available for short-lived $p$-nuclides are used in an open nonlinear model of the chemical evolution of the Galaxy in order to discuss the origin of extinct radionuclides, the stellar sources of $p$-nuclides, and the chronology of solar system formation. It is concluded that the observed abundances of $^{97}$Tc, $^{98}$Tc, $^{92}$Nb, and $^{146}$Sm in the early solar system are consistent with nucleosynthesis in type II supernovae during continuous chemical evolution of the Galaxy and a subsequent short isolation of the presolar molecular cloud from fresh nucleosynthetic inputs. However, further work on supernova models is needed before $p$-radionuclides will comprise reliable cosmochronometers. Despite these limitations, we argue that niobium-92 can be used to test whether the {\it rp}-process contributed to the synthesis of light {\it p}-nuclides in the Mo-Ru region.

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Nicolas Dauphas, Thomas Rauscher, Bernard Marty, Laurie Reisberg. 2002-11-20. Short-lived p-nuclides in the early solar system and implications on the nucleosynthetic role of X-ray binaries. https://doi.org/10.1016/s0375-9474(03)00934-5

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