High-spin states in ${}^{92}\mathrm{Nb}$ have been investigated by using in-beam $\gamma$ ray spectroscopy with the ${}^{82}\mathrm{Se}({}^{14}\mathrm{N},4\mathrm{n}){}^{92}\mathrm{Nb}$ reaction at a beam energy of 54 MeV. The positive-parity decay sequences above the previously known state ${13}^{+}$ have been extended to $I^{\pi }\ge \left({20}^{+}\right)$ by adding nineteen new $\gamma$ rays. The level structures in ${}^{92}\mathrm{Nb}$ have been interpreted in terms of the shell model calculations performed in the configuration space $\pi (1f_{5/2},2p_{3/2},2p_{1/2},1g_{9/2})$ for the protons and $\nu (2p_{1/2},1g_{9/2},1g_{7/2},2d_{5/2})$ for the neutrons. The calculated results show that the inclusion of proton core excitation relative to the $Z=38$ subshell closure and neutron particle-hole excitation for the $N=50$ shell closure are essential to adequately describe the experimental high-spin states at $I\approx (18–20)\hslash$ with excitation energies above 8.5 MeV.

• Received 23 January 2019

DOI:https://doi.org/10.1103/PhysRevC.100.014325