First complete set of spin3/2nuclear scattering analyzing powers

Abstract

The first complete set of analyzing powers for any nuclear spin $\frac{3}{2}$ beam is reported. Analyzing powers and elastic cross section are presented for ${}^{4}\mathrm{He}{(}^{7}\mathrm{Li}\ensuremath{\rightarrow}{,}^{7}\mathrm{Li}{)}^{4}\mathrm{He}$ at the two center of mass energies of 11.5 and 16.5 MeV. An optical model analysis of these data shows the need for spin-orbit and second rank tensor potentials in addition to real and imaginary central potentials. The inclusion of triton transfer improves the description of the large angle elastic scattering cross section but has little impact on the calculated analyzing powers. The description of the third rank analyzing powers ${\mathrm{iT}}_{31}$ and ${\mathrm{iT}}_{33}$ is poor at small angles, and no combination of potentials including a large third rank potential is able to describe them. No real evidence for the presence of a third rank potential is found.