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High-spin states in $^{84}\mathrm{Rb}$ have been studied using the $^{76}\mathrm{Ge}(^{11}\mathrm{B}$, $3n$) reaction at a beam energy of 36 MeV. A pair of nearly degenerate positive-parity doublet bands have been extended and interpreted as candidate chiral doublet bands based on their experimental properties. This interpretation is supported by the triaxial relativistic mean-field theory and the triaxial particle-rotor model calculations. The systematic comparison of the candidate chiral bands in the $A\ensuremath{\approx}80$ mass region are also discussed. This work is the first observation of candidate chiral doublet bands in $Z=37$ Rb isotopes and extends the boundaries of the chiral nuclei in the $A\ensuremath{\approx}80$ mass region.

CITATION: Liu, C. et al. 2019. New candidate chiral nucleus in the A≈80 mass region: 82 35Br47. Physical Review C, 100(5). doi:10.1103/PhysRevC.100.054309

CITATION: Li, C. G. et al. 2019. “Stapler” mechanism for a dipole band in 79Se. Physical Review C, 100(4). doi:10.1103/PhysRevC.100.044318

CITATION: Liu, L., et al. 2018. Evolution from quasivibrational to quasirotational structure in 155Tm and yrast 27/2− to 25/2− energy anomaly in the A ≈ 150 mass region. Physical Review C, 97(4):044306, doi:10.1103/PhysRevC.97.044306.

CITATION: Niu, C. Y., et al. 2018. Spectroscopic study of the possibly triaxial transitional nucleus 75Ge. Physical Review C, 97(3):034322, doi:10.1103/PhysRevC.97.034322.

High-spin states in $^{155}\mathrm{Yb}$ have been studied via the $^{144}\mathrm{Sm}(^{16}\mathrm{O},5n)^{155}\mathrm{Yb}$ reaction at a beam energy of 118 MeV. One negative-parity and one positive-parity cascade built on the $\ensuremath{\nu}{f}_{7/2}$ and $\ensuremath{\nu}{i}_{13/2}$ states, respectively, are established for the first time. The structures observed in $^{155}\mathrm{Yb}$ are compared with those in the neighboring $N=85$ isotones and with semiempirical shell-model (SESM) calculations. According to adiabatic and configuration-fixed constrained triaxial covariant density functional theory (CDFT) calculations, a coexistence of prolate and oblate shapes is predicted to exist in $^{155}\mathrm{Yb}$.

High-spin states of $^{115}\mathrm{In}$ have been studied using the $^{114}\mathrm{Cd}$ ($^{7}\mathrm{Li},\ensuremath{\alpha}2\mathrm{n}$) reaction at a beam energy of 48 MeV. A total of 13 new transitions have been observed and added to the level scheme of $^{115}\mathrm{In}$. Most of the states in $^{115}\mathrm{In}$ can be interpreted in terms of the weak coupling of a ${g}_{9/2}$ proton hole to the core states of $^{116}\mathrm{Sn}$ or a ${g}_{7/2}$ proton to the core states of $^{114}\mathrm{Cd}$. A $\ensuremath{\Delta}I=1$ band with the $\ensuremath{\pi}{({g}_{9/2})}^{\ensuremath{-}1}\ensuremath{\bigotimes}\ensuremath{\nu}{({h}_{11/2})}^{2}$ configuration was suggested as an oblate band built on the ``stapler'' mechanism with the aid of the tilted axis cranking model based on covariant density functional theory.

Excited states of ${}^{116}$Sb were investigated using in-beam $\ensuremath{\gamma}$-ray spectroscopy techniques with the ${}^{114}$Cd(${}^{7}$Li, $5n$) reaction. About 25 new states and 35 new transitions were added into the level scheme of ${}^{116}$Sb. The previously known two rotational bands based on the $\ensuremath{\pi}{g}_{9/2}^{}{}^{\ensuremath{-}1}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$ and $\ensuremath{\pi}{g}_{9/2}^{}{}^{\ensuremath{-}1}\ensuremath{\bigotimes}\ensuremath{\nu}{d}_{5/2}$ configurations have been extended up to (16)${}^{\ensuremath{-}}$ and (13)${}^{+}$ states, respectively. A new $\ensuremath{\Delta}I=1$ band was identified, and interpreted in terms of the triaxial particle rotor model calculations.

Excited states of $^{118}\mathrm{Sb}$ were populated via the $^{116}\mathrm{Cd}$$(^{7}\mathrm{Li}$,5n)$^{118}\mathrm{Sb}$ fusion-evaporation reaction at a beam energy of 50 MeV. The previously known level scheme has been considerably extended, and about 36 new transitions were added into the level scheme of $^{118}\mathrm{Sb}$. One new rotational band has been identified, and assigned the $\ensuremath{\pi}{g}_{9/2}^{\ensuremath{-}1}\ensuremath{\bigotimes}\ensuremath{\nu}{g}_{7/2}$ configuration. The configuration-fixed constrained triaxial relativistic mean-field approaches and the particle-rotor model calculations are employed for analysis of the level structure of $^{118}\mathrm{Sb}$.

Excited states of $^{118}\mathrm{Sn}$ have been populated in the $^{116}\mathrm{Cd}$($^{7}\mathrm{Li}$,$1p4n$) reaction with a beam energy of $50$ MeV. The previously known level scheme is extended in the low-spin region as well as to higher spins. The systematic behavior of the intruder deformed bands in the Sn isotopes is discussed. Total Routhian surface calculations and configuration-fixed constrained triaxial relativistic mean-field approaches are employed for analysis of the nuclear structure of $^{118}\mathrm{Sn}$.