Proton states inY85

The ${}_{}{}^{84}{}_{}{}^{}\mathrm{Sr}({}_{}{}^3{}_{}{}^{}\mathrm{He}, d){}_{}{}^{85}{}_{}{}^{}\mathrm{Y}$ reaction has been studied at a bombarding energy of 18 MeV to extend the systematics of proton states in the odd-$A$ yttrium nuclei. Thirty-seven states in the previously uninvestigated ${}_{39}{}^{85}{}_{}{}^{}\mathrm{Y}_{46}^{}{}_{}{}^{}$ were observed. A distorted-wave analysis was used to determine $l$ values and spectroscopic strengths. The ground state of ${}_{}{}^{85}{}_{}{}^{}\mathrm{Y}$ is assigned $J^{\pi }=\frac{1}{2^{-}}$ and the first excited state (at 20 keV) $\frac{9}{2^{+}}$. The results are compared with previous (${}_{}{}^3{}_{}{}^{}\mathrm{He}$, $d$) reaction studies on ${}_{}{}^{86}{}_{}{}^{}\mathrm{Sr}$ and ${}_{}{}^{88}{}_{}{}^{}\mathrm{Sr}$.