Structure of dipole bands in doubly odd Ag102

Abstract

Excited states in the transitional doubly odd $^{102}\mathrm{Ag}$ nucleus were populated in the $^{75}\mathrm{As}(^{31}\mathrm{P},p3n)$ fusion-evaporation reaction using the 125 MeV incident $^{31}\mathrm{P}$ beam. The subsequent deexcitations were investigated through in-beam $\ensuremath{\gamma}$-ray spectroscopic techniques using the Indian National Gamma Array spectrometer equipped with 21 clover Ge detectors. The level scheme in $^{102}\mathrm{Ag}$ has been established up to excitation energy $\ensuremath{\sim}6.5$ MeV and angular momentum $19\ensuremath{\hbar}$. The earlier reported level scheme is considerably extended and modified to result in a pair of nearly degenerate negative-parity dipole bands. Lifetime measurements for the states of these two dipole bands have been performed by using the Doppler-shift attenuation method. The two nearly degenerate bands exhibit different features with regard to kinetic moment of inertia, and the reduced transition probabilities $\mathrm{B}(M1)$ and $\mathrm{B}(E2)$, which do not favor these to be chiral partners. These bands are discussed in the framework of the hybrid version of tilted-axis cranking (tac) model calculations and assigned the $\ensuremath{\pi}{g}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$ and $\ensuremath{\pi}{g}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}{({d}_{5/2}/{g}_{7/2})}^{2}$ configurations. The tac model calculations are extended to the nearly degenerate bands observed in the heavier doubly odd $^{104--108}\mathrm{Ag}$ isotopes.