On the nature of the 17 $\mu$s isomer of the $^{133}$Sb valence nucleus

The decay of the 17 $\mu$s isomer of $^{133}$Sb was re-investigated experimentally. It was produced by thermal neutron induced fission of $^{241}$Pu. Its detection is based on time correlation between fission fragments selected by the LOHENGRIN spectrometer at ILL (Grenoble), and the $\gamma$-rays, and conversion electrons from the isomer. The interpretation of the level scheme is based on shell model calculations, where empirical two-body matrix elements were employed. The good agreement between theory and experiment suggests that the isomer is the 21/2$^+$ member of the 2p-1h $\pi g_{7/2}\nu(f_{7/2}h_{11/2}^{-1})$ configuration