Neutron and proton transition densities fromS32,34(p,p’) atEp=318 MeV. II. Neutron densities forS34

Abstract
Differential cross sections and analyzing powers for low-lying states of S34 were measured using 318 MeV protons. Neutron transition densities for the 21+ and 22+ states were fitted to the data using general expansions which permit evaluation of uncertainties due to statistical and normalization errors, penetrability and distortion, and incompleteness in momentum space. We find that the experimental densities agree well with the shell model for the first 2+ state, but that the neutron density for the second 2+ state is distinctly different in shape. We also find Mn/Mp=+0.27(6) for the 22+ state, in qualitative agreement with electromagnetic results for A=34 but in marked disagreement with the shell-model prediction of Mn/Mp=-0.61. A detailed analysis of earlier data for 650 MeV, originally described as qualitatively consistent with the shell model, is also presented and shows that these data are more consistent with the present results. The shape of the isoscalar density for the 22+ state of S34 cannot be reproduced with the sd shell, supplemented by surface-peaked core polarization, but can be reproduced if an empirical (1f)2 contribution is admitted. Shell-model calculations were performed for other 2+ and 4+ states of S34, but give cross sections well below the (p,p’) data for all but the lowest 2+ state. The data for the lowest 1, 3, and 5 states in both S34 and S32 are very similar.