To calculate more reliable stellar evolution scenarios, astrophysicists need to know as precisely as possible the rate of carbon fusion.
Nuclear physicists who reproduce stellar energy conditions in the laboratory, through collisions between a particle beam and a target, are able to provide direct measurements of carbon fusion rates.
The STELLA team of the IPHC laboratory (CNRS-IN2P3), successfully conducted an experiment with the assistance of IJCLab on the particle accelerator Andromède, a facility specially designed to provide an extremely intense carbon beam. Before everyone else, the team obtained the most reliable measurements of cross-section of carbon 12 + carbon 12 fusion reaction at low energies, thus demonstrating a difference approaching an order of magnitude with the reference values used by astrophysicists in their models of star evolution.
See French article on CNRS-IN2P3 : https://in2p3.cnrs.fr/fr/cnrsinfo/la-fusion-12c12c-dans-les-etoiles-massives-serait-plus-faible-quattendu