Nuclear Structure Studies ofSr88andY89Using 19-MeV Proton Scattering and theSr88(He3, d)Reaction

Elastic and inelastic angular distributions were obtained for 19-MeV protons scattered from ${\mathrm{Sr}}^{88}$ and ${\mathrm{Y}}^{89}$. Deuteron angular distributions were also obtained from the ${\mathrm{Sr}}^{88}({\mathrm{He}}^3, d)$ reaction and used to study the single-particle nature of the excited states of ${\mathrm{Y}}^{89}$. Spectroscopic information was obtained by comparing the inelastic proton distributions with predictions of the distorted-wave theory using a real collective-model form factor. Proton angular distributions of the low-lying states of ${\mathrm{Y}}^{89}$ and ${\mathrm{Sr}}^{88}$ were compared to determine if the states of ${\mathrm{Y}}^{89}$ could be explained as the weak coupling of the $2p_{\frac{1}{2}}$ proton to the core-excited states of ${\mathrm{Sr}}^{88}$. The states at 1.49 and 1.74 MeV in ${\mathrm{Y}}^{89}$ do not appear to be described adequately as core-excited states, while the states at 2.22 (or 2.87) and 2.52 MeV do. The proton angular distributions for those states which could be described in terms of simple shell-model configurations were also analyzed with the distorted-wave theory using shell-model form factors.