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

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 Tc-97, Te-98, Nb-92, and Sm-146 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 rp-process contributed to the synthesis of light p-nuclides in the Mo-Ru region.