We report the first g factor measurement on microsecond isomers of neutronrich nuclei produced in projectile-fragmentation reactions at intermediate energies. The nuclides in the vicinity of 68 Ni were produced and spin oriented following the fragmentation of a 76 Ge, 61.4 MeV u −1 beam at GANIL. The LISE spectrometer was used to select the nuclei of interest. The time-dependent perturbed angular distribution (TDPAD) method was applied in combination with the heavy-ion-gamma correlation technique to measure the g factors of 69m Cu (J π = 13/2 + , T 1/2 = 350 ns) and 67m Ni (J π = 9/2 + , T 1/2 = 13.3 µs). Specific details of the experimental technique and the comparison of the results (|g(69m Cu)| = 0.225(25) and |g(67m Ni)| = 0.125(6)) with theoretical calculations are discussed. These results provide another indication of the importance of proton excitations across the Z = 28 shell gap.

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The quadrupole moment of the 11(-) isomer in 196Pb has been measured by the level mixing spectroscopy method. This state has a pi(3s(-2)(1/2)1h(9/2)1i(13/2))11(-) configuration which is involved in most of the shears band heads in the Pb region. The first directly measured value of Q(s)(11(-)) = (-)3.41(66) b, coupled to the previously known quadrupole moment of the nu(1i(-2)(13/2))12(+) isomer allows us to estimate the quadrupole moment of the 16(-) shears band head as Q(s)(16(-)) = -0.32(10) b. The experimental values are compared to tilted axis cranking calculations, giving insight into the validity of the additivity approach to couple quadrupole moments and on the amount of deformation in the shears bands.

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