¹Kurt Marti,²Mario Fischer-Gödde,³Carina Proksche
The Astrophysical Journal 956, 7 Open Access Link to Article [DOI 10.3847/1538-4357/acee81]
¹Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0314, USA
²Universität zu Köln, Institut für Geologie und Mineralogie, Zülpicher Str. 49b, D-50674 Köln, Germany; mfisch48@uni-koeln.de
³Geo Zentrum Nordbayern, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schlossgarten 5, D-91054 Erlangen, Germany

Anomalies in isotopic abundances of Mo and Ru in solar system matter were found to document variable contributions of the nucleosynthetic s-process component. We report isotopic relations of ⁹²Mo versus ¹⁰⁰Ru in meteorites from chondritic parent bodies, iron meteorites, and achondrites that reveal deviations from expected s-process abundance variations. We show that two p-process isotopes ⁹²Mo and ⁹⁴Mo require the presence of distinct p-process components in meteoritic materials. The nucleosynthetic origin of abundant magic (N = 50) p-process nuclides, covering the mass range of Zr, Mo, and Ru, has long been an enigma, but contributions by several recognized pathways, including alpha and νp-antineutrino reactions on protons, may account for the observed relatively large solar system abundances. Specific core-collapse supernovae explosive regions may carry proton-rich matter. Since Mo and Ru isotopic records in solar system matter reveal the presence of more than one nucleosynthetic p-process component, these records are expected to be helpful in documenting different explosive synthesis pathways and the implied galactic evolution of p-nuclides.