Possible particle-hole intruder sequence in $^{\mathrm{83}}$Se$_{\mathrm{49}}$.

A new sequence of higher-spin levels at 1266 (7/2$^{\mathrm{+}})$, 2407 (11/2$^{\mathrm{+}})$, 3689 (15/2$^{\mathrm{+}})$, and 4673 (19/2$^{\mathrm{+}})$ has been identified in the single-neutron-hole $^{\mathrm{83}}$Se$_{\mathrm{49}}$ nucleus. This sequence feeds into the 5/2$^{\mathrm{+}}$ level at 583 keV that is strongly populated in (d,p) reaction studies and considered as a 1-particle-2-hole state connected to the known d$_{\mathrm{5/2}}$ ground state of $^{\mathrm{85}}$Se$_{\mathrm{51}}$. The data were taken using Gammasphere at the ATLAS accelerator complex at Argonne National Laboratory following the interaction of a 630-MeV $^{\mathrm{82}}$Se beam with $^{\mathrm{208}}$Pb and $^{\mathrm{238}}$U targets. These and previously identified levels in $^{\mathrm{83}}$Se will be compared to shell-model calculations. [1] Richard A. Meyer, O. G. Lein III, and E. A. Henry, Phys. Rev. C \textbf{25}, 682 (1982). [2] Luis A Montestruque et al., Nucl. Phys. \textbf{A305}, 29 (1978). [3] Marie-Genevieve Porquet et al., Eur. Phys. J. A \textbf{39}, 295 (2009).