Fine structure in the α decay of Lu156 and Ta158

Abstract

Fine structure in the α decay of high-spin states in 156 Lu and 158 Ta has been identified by means of αγcoincidence analysis. One new α decay from 156 Lu and two from 158 Ta were identified, one of which was found to populate a previously unknown state in 154 Lu. The hindrance-factor systematics from all four odd-odd, N = 85 nuclei with known α-decaying, π h 11/2 coupled states were reviewed and are discussed. These proved consistent with the previously assigned (π h 11/2 νh 9/2)10 + configuration of the α-decaying state in 156 Lu, which differs from the (π h 11/2 ν f 7/2)9 + assignments in the other three nuclei.