Evidence for a ComplexL→·S→Interaction in the Deuteron-Nucleus Optical Potential

The addition of an imaginary $\overrightarrow{\mathrm{L}}·\overrightarrow{\mathrm{S}}$ interaction to the deuteron-nucleus optical potential significantly improves the fit to cross-section and analyzing-power measurements for elastic scattering of 10-15-MeV deuterons from medium-weight nuclei. The largest improvement results from a shift of the analyzing powers toward smaller angles, relative to the cross section. The imaginary $\overrightarrow{\mathrm{L}}·\overrightarrow{\mathrm{S}}$ potential has the same sign and about one-half the strength of the real $\overrightarrow{\mathrm{L}}·\overrightarrow{\mathrm{S}}$ potential.