Spin-Orbit Splitting in Nuclei Due to Tensor Interaction

The effect of the tensor force in nuclei with closed shells plus one nucleon has been investigated using second-order perturbation theory. It is found that one can explicitly exhibit the spin-orbit splitting due to the tensor force using some simple identities. The spin-orbit splitting in ${\mathrm{He}}^5$ is computed, and found to be 3.4 Mev compared with an experimental value of 2.6 Mev.