The γ-process nucleosynthesis in core-collapse super-novae

¹ Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence Konkoly, Thege Miklós út 15-17, H-1121 Budapest, Hungary
² INAF – Osservatorio Astronomico di Roma Via Frascati 33, I-00040, Monteporzio Catone, Italy
³ NuGrid Collaboration, http://nugridstars.org
⁴ E. A. Milne Centre for Astrophysics, University of Hull, Hull HU6 7RX, UK
⁵ School of Physics and Astronomy, Monash University, VIC 3800, Australia
⁶ Eötvös Loránd University, Institute of Physics, Budapest 1117, Pázmány Péter sérány 1/A, Hungary
⁷ Institute for Nuclear Research (ATOMKI), H-4001 Debrecen, Hungary

^* e-mail: lorenzo.roberti@csfk.org

Published online: 22 March 2023

Abstract

Neutron-capture processes made most of the abundances of heavy elements in the Solar System, however they cannot produce a number of rare proton-rich stable isotopes (p–nuclei) lying on the left side of the valley of stability. The γ–process, i.e., a chain of photodisintegrations starting on heavy nuclei, is recognized and generally accepted as a feasible process for the synthesis of p–nuclei in core collapse supernovae (CCSNe). However this scenario still leaves some puzzling discrepancies between theory and observations. We aim to explore in more detail the γ–process production from massive stars, using different sets of CCSNe models and the latest nuclear reaction rates. Here we show our preliminary analysis, by identifying the γ–process sites and focusing on progenitors of CCSNe that experience a C–O shell merger just before the collapse of the Fe core.