Collaborative Research: Computational Faddeev approach to Nuclear Reactions

Ohio University, Athens OH

Investigators

Abstract

Nuclear Science is tasked with answering questions such as: (i) How did matter come into being and how does it evolve? (ii) How does subatomic matter organize itself and what phenomena emerge? (iii) How can the knowledge and technology progress provided by nuclear physics best be used to benefit society? Providing answers to these questions depends on a detailed theoretical understanding of nuclear reactions, a field in which current approaches are either outdated or limited to a small number of applications. In this larger context, this project will focus on the theoretical study of deuteron-induced reactions. Due to the short lifetimes involving exotic nuclei, direct neutron capture measurements of relevance to the origin of the heavy elements are often not possible. Indirect techniques like deuteron induced reactions are a common tool to extract the relevant astrophysical rates. These reactions are part of ongoing experimental programs at radioactive beam facilities, as well as programs at future facilities such as the Facility for Rare Isotope Beams (FRIB). As such, this project will provide theoretical support to challenging experimental programs and will provide a unique training opportunity for graduate students and post-doctoral fellows. A reliable reaction theory is critical for the understanding the data produced at experimental programs using (d,p) reactions. From a theoretical perspective, (d,p) reactions are attractive because the scattering can be reduced to an effective three-body problem. One of the most challenging aspects of solving the three-body problems for nuclear reactions is posed by the repulsive Coulomb interaction. While for light nuclei the momentum-space Faddeev equations can be treated by screening the Coulomb force, a similar approach is difficult to implement for heavy systems. Indeed, for most of the new exotic nuclei to be produced at FRIB, currently available computational methods are not adequate. This project will address this critical need and provide an implementation of an exact Faddeev method for the three-body nuclear reaction problem, in which the Coulomb force will be treated without screening.