Precise initial abundance of Niobium-92 in the Solar System and implications for <i>p</i> -process nucleosynthesis
Makiko K. Haba, Yi-Jen Lai, Jörn‐Frederik Wotzlaw, Akira Yamaguchi, Maria Lugaro, Maria Schönbächler
Abstract
Significance Niobium-92 is a short-lived p -process isotope that decays to 92 Zr with a half-life of 37 Ma. The initial 92 Nb/ 93 Nb ratio of the Solar System is crucial for utilizing the 92 Nb– 92 Zr chronometer, as it has the potential to provide information on early Solar System evolution and insights into the debated p -process nucleosynthesis. Herein, we precisely determine the initial 92 Nb/ 93 Nb ratio of the Solar System using rare minerals in meteorites. This significantly improved precision makes the 92 Nb– 92 Zr chronometer a powerful tool for providing precise ages of accretion, differentiation, and collision for asteroids and planets. Additionally, the initial ratio reveals that both type Ia supernovae and core-collapse supernovae contributed to the nucleosynthesis of the p -process isotope 92 Nb in our Solar System.