Comparison of superdeformed bands in 61Zn and 60Zn: Possible evidence for T=0 pairing

The yrast superdeformed band in 61Zn has been established using 28Si(36Ar, 2pn)61Zn and 40Ca(29Si, 2α)61Zn fusion-evaporation reactions. The excitation energy of this band was determined via two transitions that link this band to the normally deformed states. Lifetime analysis of this band resulted in a quadrupole moment of Qt=3.0±0.40.5e b, which corresponds to a deformation of β2=0.50±0.060.07. A comparison of the J(2) dynamical moments of inertia of the yrast superdeformed band in 61Zn with those in 60Zn shows a nearly complete blocking of the observed alignment in 60Zn, indicating that T=0 proton-neutron pair correlations may be present in 60Zn.