Lowest-order contributions of chiral three-nucleon interactions to pairing properties of nuclear ground states

Abstract

We perform a systematic study of the odd-even mass staggering generated using a pairing interaction computed at first order in low-momentum interactions. Building on previous work including the (nuclear plus Coulomb) two-nucleon interaction only, we focus here on the first-order contribution from chiral three-nucleon forces. We observe a significant repulsive effect from the three-nucleon interaction. The combined contribution from two- and three-nucleon interactions accounts for approximately 70% of the experimental pairing gaps. This leaves room for higher-order contributions to the pairing kernel and the normal self-energy that need to be computed consistently.

Comments: 4 pages, 2 figures. Proceedings of the International Niigata 2010 Symposium on Forefronts of Researches in Exotic Nuclear Structures, Tokamachi, Japan, March 1 - March 4, 2010. To be published in Modern Physics Letters A