The impact of tensor force on collective correlations and neutrinoless double-β decay

We carefully examined the impact of the monopole and multipole effects originating from the tensor force on both the collectivity and the matrix element for the neutrinoless double-β (0νββ) decay, using the generator-coordinate method with an effective interaction.

To analyze the effect of the tensor force, we employed an effective Hamiltonian associated with the monopole-based universal interaction that explicitly consists of the central, tensor, and spin-orbit coupling terms. The interferences among the shell structure, quadrupole collectivity, nucleon occupancy, and 0νββ matrix elements were analyzed in detail. A better understanding of the tensor force would be of great importance in reducing the theoretical uncertainty in 0νββ nuclear matrix element calculations