New measurements of the ⁶³Cu(α, γ)⁶⁷Ga reaction compared with improved calculations

¹ Tandem Accelerator Laboratory, Institute of Nuclear Physics, NCSR “Demokritos”, 15310 Aghia Paraskevi, Athens, Greece
² Department of Physics, University of Ioannina, 45110 Ioannina, Greece
³ Nuclear Data Section, Division of Physical and Chemical Sciences, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, POB 100, Vienna, Austria
⁴ Central Unit for Ion Beams and Radionuclides, Ruhr-University Bochum, 44801, Bochum, Germany
⁵ Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece

^* e-mail: marpeoviti@gmail.com

Published online: 14 March 2025

Abstract

One of the challenges of nuclear astrophysics is understanding the observed abundances of the p-process nuclei. Nucleosynthesis calculations typically employ an extended reaction network involving tens of thousands of reactions and thousands of isotopes. As it is impossible to experimentally investigate such a vast number of reactions, these calculations rely heavily on cross sections derived from the Hauser-Feshbach (HF) theory. To improve the predictive power of the HF theory, it is important to provide updated parameterization of the incorporated models, validated comprehensively using experimental data. In this paper, we report on a new measurement of the ⁶³Cu(α, γ)⁶⁷Ga reaction cross-section, at energies relevant to the p-process nucleosynthesis. The purpose of the measurement was to further improve the global α-nucleus Optical Model Potential (αOMP). HF calculations were performed with the TALYS code (version 1.96) probing the sensitivity to all the important ingredients of the calculations including the Optical Model Potentials (OMP), Nuclear Level Densities (NLD), and γ-ray Strength Functions (γSF). New optimized parameters are proposed for the global semi-microscopic αOMP. The results are preliminary.