Isomeric Transition inSb122

An investigation of the two previously reported gamma radiations (61 kev and 75 kev) of ${\mathrm{Sb}}^{122m}$ (3.5 min) revealed that the 75-kev transition has a $K$ conversion coefficient which agrees with that of an $E2\mathrm{}$ transition but a half-life in agreement with that of an $L=3\mathrm{}$ transition. Delayed coincidence measurements disclosed a state with a 1.8-μsec half-life which is populated by the 75-kev transition. This decays through the emission of a 61-kev gamma ray. This transition exhibits a $K$ conversion coefficient in agreement with that of an $E1\mathrm{}$ transition although the lifetime is more compatible with an $L=2\mathrm{}$ assignment. These transitions are delayed by factors of ≥${10}^6$.