The inclusive transverse response of nuclear matter

Abstract

The electromagnetic inclusive transverse response of nuclear matter at saturation density is studied within the correlated basis function perturbation theory for momentum transfers q from 300 to 550 MeV/c. The correlation operator includes a Jastrow component, accounting for the short range repulsion, as well as longer range spin, tensor and isospin ones. The Schiavilla- Pandharipande-Riska model for the two-body electromagnetic currents, satisfying the continuity equation with realistic v_14 potentials, is adopted. Currents due to intermediate Delta-isobar excitations, are also included. The global contribution of the two-body currents turns out to be positive and provides an enhancement of the one-body transverse response ranging from about 20% for the lower momenta to about 10% for the higher ones. This finding is in agreement with the Green's Function Monte Carlo studies of the transverse Euclidean response in A=3,4 nuclei and contradicts previous results obtained within the Fermi gas and shell models. The tensor-isospin component of the correlation is found to be the leading responsible for such a behavior. The nuclear matter response is compared to recent experimental data on 40Ca and 56Fe.