Effect of the tensor force on the charge-exchange spin-dipole excitations of 208Pb

TL;DR

This study investigates how tensor interactions influence charge-exchange spin-dipole excitations in 208Pb using a self-consistent Skyrme HF+RPA approach, revealing multipole-dependent effects and improving experimental agreement.

Contribution

It demonstrates, for the first time, the multipole-dependent impact of tensor correlations on SD excitations within a self-consistent framework.

Findings

Tensor correlations cause softening of 1- states.

Tensor correlations cause hardening of 0- and 2- states.

Results align better with recent experimental data.

Abstract

The charge-exchange spin-dipole (SD) excitations of 208Pb are studied by using a fully self-consistent Skyrme Hartree-Fock plus Random Phase Approximation (HF+RPA) formalism which includes the tensor interaction. It is found, for the first time, that the tensor correlations have a unique, multipole-dependent effect on the SD excitations, that is, they produce softening of 1- states, but hardening of 0- and 2- states. This paves the way to a clear assessment of the strength of the tensor terms. We compare our results with a recent measurement, showing that our choice of tensor terms improves the agreement with experiment. The robustness of our results is supported by the analytic form of the tensor matrix elements.