ReactionsNi58(He3,He3') andNi58(He3,α)at 51.3 MeV

Abstract

Differential cross sections were measured for elastic and inelastic scattering of 51.3-MeV ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ from ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$, and for ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}({}_{}{}^3{}_{}{}^{}\mathrm{He},\alpha )$. The elastic scattering was analyzed in terms of the optical model with a Woods-Saxon potential. Several satisfactory sets of parameters were obtained. The inclusion of a spin-orbit term with $V_s\simeq 2.9$ MeV improved the best fits. The inelastic scattering events were treated as one-phonon collective transitions in the distorted-wave approximation, using complex coupling. The $\beta R_0^{}{}_{}{}^{\prime }$ agreed well with deformation lengths from other experiments. No improvement in the fit to the $2^{+}$ angular distribution was found in calculations with unequal real and imaginary deformations. The (${}_{}{}^3{}_{}{}^{}\mathrm{He},\alpha )$) results were compared with zero-range distorted-wave predictions, using a previously obtained empirical normalization. The spectroscopic factors are in good agreement with other experiments and sum-rule expectations.