Detailed structure information on ${}^{133}\mathrm{Sb}$ has been obtained in a high-sensitivity study of the ${}^{133}\mathrm{Sn}$ decay. The $d_{3/2}$ single proton state was found at 2439.5 keV. The $\gamma$-ray branching gives $B({M1;d}_{3/2}\to d_{5/2})/B({E2;d}_{3/2}\to g_{7/2})=0.037\mathrm{}\left(3\right)$ in W.u. For the $h_{11/2}$ state, a half-life of 11.4(4.5) ps was measured for the first time, giving $B(M2;h_{11/2}\to g_{7/2})=0.55\mathrm{}\left(22\right)\mathrm{W}.\mathrm{u}.\mathrm{}$ and $B(E3;h_{11/2}\to d_{5/2})=22\mathrm{}\left(13\right)\mathrm{W}.\mathrm{u}.\mathrm{}$ The single proton transition strengths in ${}^{133}\mathrm{Sb}$ and ${}^{209}\mathrm{Bi}$ are found to be remarkably similar. In contrast, the spin-orbit splitting in these nuclei show important differences.

• Received 4 November 1997

DOI:https://doi.org/10.1103/PhysRevLett.80.5504