A new ¹²C+¹²C reaction rate: Impact on stellar evolution

¹ Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France
² Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles, CP 226, 1050, Brussels, Belgium
³ University of Strasbourg Institute of Advanced Studies (USIAS), Strasbourg, France
⁴ Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA
⁵ Department of Physics & Astronomy, Texas A&M University, College Station, Texas 77843, USA
⁶ Department of astronomy, University of Geneva, chemin Pegasi 51, 1290 Versoix, Switzerland
⁷ Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom

^* e-mail: emma.monpribat@iphc.cnrs.fr

Published online: 22 March 2023

Abstract

Among the reactions driving stellar evolution during carbon burning, ¹²C + ¹²C fusion provides the key ingredients. This system reveals many resonances, but also regions with suppressed fusion cross-sections. The reaction was recently measured by the STELLA collaboration utilizing the gammaparticle coincidence technique for precise cross-section measurements reaching down to the Gamow window of massive stars. From the experimental data, reaction rates were determined by approximating a hindrance parametrization and by adding on top a resonance at the lowest measured energy. The impact of these reaction rates on the evolution of massive stars was explored with models of 12 and 25 M_⊙ using the stellar evolution code GENEC, and a detailed study of the resulting nucleosynthesis with a 1454 elements network was performed. The sensitivity of the STELLA experimental cross-sections on the temperature range for C-burning for the stellar models studied were presented. The final abundances and their impacts on stellar evolution were discussed.