Electromagnetic processes in a χEFT framework

Abstract

Recently, we have derived a two–nucleon potential and consistent nuclear electromagnetic currents in chiral effective field theory with pions and nucleons as explicit degrees of freedom. The calculation of the currents has been carried out to include N3LO corrections, consisting of two–pion exchange and contact contributions. The latter involve unknown low-energy constants (LECs), some of which have been fixed by fitting the np S- and P-wave phase shifts up to 100 MeV lab energies. The remaining LECs entering the current operator are determined so as to reproduce the experimental deuteron and trinucleon magnetic moments, as well as the np cross section. This electromagnetic current operator is utilized to study the nd and n3He radiative captures at thermal neutron energies. Here we discuss our results stressing on the important role played by the LECs in reproducing the experimental data.