Lifetimes and structure of excited states of115Sb

Lifetimes of excited states of ${}^{115}\mathrm{Sb}$ were measured by the Doppler shift attenuation method in the $(\alpha ,2n\gamma )$ reaction at $E_{\alpha }$ = 27.2 MeV. The experimental level scheme and the electromagnetic transition probabilities have been interpreted in terms of the interacting boson-fermion model. A reasonable agreement with the experiment was obtained for the positive-parity states. The experimental data also show the applicability of the cluster-vibrational model for the mixing of two ${9/2}^{+}$ states having different intrinsic configurations.