Excited states of 129In populated following the β-decay of 129Cd were experimentally studied with the GRIFFIN spectrometer at the ISAC facility of TRIUMF, Canada. A 480-MeV proton beam was impinged on a uranium carbide target and 129Cd was extracted using the Ion Guide Laser Ion Source (IG-LIS). β- and γ-rays following the decay of 129Cd were detected with the GRIFFIN
spectrometer comprising the plastic scintillator SCEPTAR and 16 high-purity germanium (HPGe) clover-type detectors. From the β-γ-γ coincidence analysis, 32 new transitions and 7 new excited states were established, expanding the previously known level scheme of 129In. The log f t values deduced from the β-feeding intensities suggest that some of the high-lying states were populated by
the ν0g7/2 → π0g9/2 allowed Gamow-Teller (GT) transition, which indicates that the allowed GT transition is more dominant in the 129Cd decay than previously reported. Observation of fragmented Gamow-Teller strengths is consistent with theoretical calculations