Abstract
Beta-decay spectroscopy of the 187 Ta ground state was performed at KISS. β-delayed γ-rays corresponding to the previously reported in-beam transitions were observed. The β-decay half-life of the 187 Ta ground state was determined to be 283(10) s by analyzing a time spectrum of β-γ coincidence events. The β-decay branching ratio and log(f t) values were evaluated for the first time. Based on the newly evaluated log(f t) values of > 6.0 and a decay scheme, spin-parity values of I π = 7/2 + originating from the odd-proton orbit π7/2[404] were assigned with high confidence, which is consistent with the systematics of neighboring odd-A nuclides.