New insights into the role of nucleon exchange in nuclear fusion

Low-energy nuclear fusion reactions can provide clean energy. In stars, low-energy fusion reactions during the carbon and oxygen burning phases are critical for stellar evolution. These reactions also provide valuable insights into the exotic processes that occur in the inner crust of neutron stars as they accumulate matter.

However, scientists do not fully understand the underlying dynamics that govern these reactions. The key to unlocking the fusion process is understanding how nucleons move between two fusion nuclei. As nuclei get close enough for nuclear forces to become effective, neutrons and protons can migrate from one nucleus to another. This movement potentially facilitates the melting process.

A recent study has explored the impact on low-energy fusion processes of isospin composition. This is a key nuclear property that distinguishes protons from neutrons. The researchers used computational techniques and theoretical modeling to investigate the fusion of different nuclei with different isospin configurations. The results show that the isospin composition of the nuclei in a fusion reaction plays a crucial role in understanding the reaction. The paper was published in the journal Physical examination C.

In this study, researchers at Fisk University and Vanderbilt University used high-throughput computational and theoretical modeling techniques to perform a detailed many-body study of how isospin dynamics affects nuclear fusion at low energies in a series isotopes. The study also looked at how the shape of the nuclei involved affects these dynamics. In systems where the nuclei are not symmetric, isospin dynamics becomes particularly important, often leading to a lower fusion barrier, especially in neutron-rich systems. This phenomenon can be explored using facilities that specialize in generating beams composed of exotic and unstable cores.

The findings provide critical insights into the fundamental nuclear processes that govern these reactions, which have far-reaching implications for fields such as nuclear physics, astrophysics and, perhaps one day, fusion-based energy.