Hindered Gamow-Teller Decay to the Odd-Odd N=Z 62Ga: Absence of Proton-Neutron T=0 Condensate in A=62.

Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, Jπ=0+ ground state of 62Ge into excited states of the odd-odd N=Z nucleus 62Ga. The experiment is performed at GSI Helmholtzzentrum für Shwerionenforshung with the 62Ge ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14)??ms is measured for the 62Ge ground state. Six excited states of 62Ga, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T=0 proton-neutron correlations in 62Ga. [ABSTRACT FROM AUTHOR]