Single-neutron excitations in neutron-rich Ge 83 and Se 85

The $^{2}\mathrm{H}$($^{82}\mathrm{Ge}$,$p$)$^{83}\mathrm{Ge}$ and $^{2}\mathrm{H}$($^{84}\mathrm{Se}$,$p$)$^{85}\mathrm{Se}$ reactions were studied with radioactive beams of $^{82}\mathrm{Ge}$ and $^{84}\mathrm{Se}$ at beam energies of ${E}_{\mathrm{beam}}=330$ and 380 MeV, respectively. Excitation energies, proton angular distributions, and asymptotic normalization coefficients have been determined for the lowest lying states of $^{83}\mathrm{Ge}$ and $^{85}\mathrm{Se}$. Spectroscopic factors have also been extracted under normal assumptions of the bound-state potential properties in the distorted waves Born approximation analysis. However, the peripheral character of the measurements leads to large uncertainties in this extraction. Shell-model calculations have been performed in the region above $^{78}\mathrm{Ni}$, comparing the single-particle properties of the even-$Z,N=51$ nuclei up to $^{91}\mathrm{Zr}$ and including $^{83}\mathrm{Ge}$ and $^{85}\mathrm{Se}$. Direct-semidirect neutron capture calculations to $^{83}\mathrm{Ge}$ and $^{85}\mathrm{Se}$ have also been performed using the spectroscopic input from these $(d,p)$ reaction measurements.