β decay of Cd¹²⁹ and excited states in In¹²⁹

The β decay of Cd¹²⁹, produced in the relativistic fission of a U²³⁸ beam, was experimentally studied at the RIBF facility at the RIKEN Nishina Center. From the γ radiation emitted after the β decays, a level scheme of In¹²⁹ was established comprising 31 excited states and 69 γ-ray transitions. The experimentally determined level energies are compared to state-of-the-art shell-model calculations. The half-lives of the two β-decaying states in Cd¹²⁹ were deduced and the β feeding to excited states in In¹²⁹ were analyzed. It is found that, as in most cases in the Z<50, N≤82 region, both decays are dominated by the ν0g_7/2→π0g_9/2 Gamow-Teller transition, although the contribution of first-forbidden transitions cannot be neglected.