Structure of the isomeric states in Sb123,125

Excited states in Sb123,125 have been studied following the Sn122,124(Li7,α2n)Sb123,125 reactions at beam energies of 35 and 37 MeV, respectively. Conversion coefficients for transitions depopulating isomeric states in Sb125 have been measured using an electron spectrometer. This has allowed firm Jπ assignments to be made and enabled the structure of the isomeric states to be compared with those in 121,127-131Sb and in the neighboring even-A tin isotopes. The half-lives of the Jπ=232+ isomeric states in Sb123 and Sb125 have been measured to be 66(4) μs and 272(16) ns, respectively. The half-lives of the Jπ=192+,192-, and 152- states in Sb125 have been measured as 31(2) ns, 28.0(7) μs, and 4.1(2) μs, respectively. The transition probabilities for the transitions depopulating these states are compared with those in 121,127-131Sb and with the results of shell-model calculations using the Oxbash code and the SN100PN interaction in a restricted model space.