Medium corrections to the tensor interaction in nuclei: Energy difference of T = 1 and T = 0 Jπ = 0- in 16O

It has been shown in the past that in a shell model calculation, restricted to 1ℎω 1p - 1h configurations, the energy splitting between the lowest Jπ = 0-, T = 0 and Jπ = 0-, T = 1 states in 16O is mainly due to the tensor component of the nucleon-nucleon interaction. In this work, the authors extend the calculation to include 3ℎω 2p - 2h and 3p - 3h configurations. They use realistic G matrices derived from various one-boson exchange potentials, taking into account the effects of the Dirac-Brueckner-Hartree-Fock approach, i.e., a modification of the Dirac spinors for the nucleons in the medium. It is found that the splitting is rather sensitive to the long-range components of the isovector tensor force. The splitting is reduced considerably by including 2p - 2h configurations. 23 refs., 1 fig., 3 tabs