Properties of the collective bands in ${}^{125}\mathrm{I},$ populated in ${}^{123}\mathrm{Sb}(\alpha ,2n\gamma {)}^{125}\mathrm{I}$ reaction at $E=30\mathrm{}\hspace{0.5em}\mathrm{MeV},$ have been studied from $\gamma$-ray angular distributions and excitation functions. Spins and parities are inferred for several states. New $E2/M1\mathrm{}$ mixing ratios are deduced for five transitions. A three-quasiparticle collective band is proposed on the basis of these and earlier results. The shapes of the ground state yrast band and the $g_{9/2}$ band are discussed, providing evidence for the coexistence of prolate and oblate collective states.

• Received 7 July 2000

DOI:https://doi.org/10.1103/PhysRevC.63.014313