100 Years of Nuclear Isomers

The neutron-rich hole nuclei of A=128 are studied by large-scale shell-model calculations employing the extended pairing plus multipole-multipole force model. The high-spin energy levels of ${}^{128}$In and beta decay are investigated deeply between these A=128 nuclei. The excited energy and logft values of beta decay are predicted in the final states of ${}^{128}$Ag, ${}^{128}$Cd, and ${}^{128}$In by the cascaded decays calculated in A=128 hole nuclei. The monopole effects are investigated carefully in the beta decay process from ground state 0${}^{+}$ of ${}^{128}$Cd to the 1${}^{+}$ levels of ${}^{128}$In, and its half-life is affected by monopole corrections acting on the configuration of final states. The high-spin isomers of ${}^{128}$Cd are predicted as a spin-trap isomer feeding the exist high-spin 16${}^{+}$ of ${}^{128}$In by beta decay.