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The neutron-rich isotopes of cadmium up to the N=82 shell closure have been investigated by high-resolution laser spectroscopy. Deep-uv excitation at 214.5 nm and radioactive-beam bunching provided the required experimental sensitivity. Long-lived isomers are observed in 127Cd and 129Cd for the first time. One essential feature of the spherical shell model is unambiguously confirmed by a linear increase of the 11/2- quadrupole moments. Remarkably, this mechanism is found to act well beyond the h11/2 shell. [ABSTRACT FROM AUTHOR]

The quadrupole interaction of the 11- and 12+ isomers in 192,194Pb nuclei has been investigated in the electric field gradient of metallic Bi polycrystalline lattice by the method of time-differential observation of the γ-rays perturbed angular distribution. The electric field gradient strength of the host Bi lattice has been calibrated by using as probe the 12+ isomer in 194Pb. The intrinsic quadrupole moments derived for the 11- isomers described by the π(1h9/21i13/2) intruder configuration are compared with the predictions of mean-field and interacting boson models. [ABSTRACT FROM AUTHOR]

We report on the first use of post-accelerated radioactive isomeric beams. Long-lived isomeric states in 68Cu and 70Cu have been produced and separated at ISOLDE, CERN. Subsequently they were post-accelerated to 2.86 MeV/u and sent to a target in the center of the MINIBALL spectrometer, used for the detection of the γ-rays of interest. The preliminary results from the Coulomb excitation of the Iπ=6-, 1+ states in 68Cu and the Iπ=6- one in 70Cu, compared to a large-scale shell model calculations, hint the importance of the excitations across the Z=28 gap for the understanding of the nuclear structure in the neutron-rich N=40 region. [ABSTRACT FROM AUTHOR]

We report results from a pioneering experiment to measure the g factors of isomeric states of neutron-rich nuclei around [sup 68]Ni, far from the valley of β stability. For the first time, the timedependent perturbed angular distribution method was applied in combination with the heavy-ion-γ correlation technique to study g factors of spin-aligned isomers produced in a projectile fragmentation reaction and mass-separated. Some technical aspects are discussed and illustrated with preliminary results. [ABSTRACT FROM AUTHOR]

The quadrupole interaction of high-spin isomers in 193Pb implanted into solid Hg cooled at a temperature T = 170 K has been investigated by the time-differential perturbed γ-ray angular-distribution method. Spectroscopic quadrupole moment values of |Qs| = 0.22(2) eb and 0.45(4) eb have been deduced for the 21/2- and 33/2+ three-neutron states, respectively. A much higher value |Qs| = 2.84(26) eb has been determined for the 29/2- isomer, the band head of a magnetic rotational band. [ABSTRACT FROM AUTHOR]

Post-accelerated isomerically purified radioactive beams, available at the CERN On-Line Isotope Mass Separator facility using the resonant ionization laser technique, have been used to study the Coulomb excitation of the Iπ = 3- state in 70Cu (Z = 29, N = 41). While first results using a Iπ =6- beam were reported previously, the present complementary experiment allows us to complete the study of the multiplet of states (3-, 4- ,5-,6-) arising from the π2p3νlg9/2 configuration. Besides the known γ-ray transition deexciting the 4- state, a ground-state γ ray of 511(3) keV was observed for the first time and was unambiguously associated with the 5- state deexcitation. This observation fixes the energy, spin, and parity of this state, completing the low-energy level scheme of 70Cu. B(E2) values for all possible E2 transitions within the multiplet were determined. A comparison with large-scale shell model calculations using different interactions and valence spaces shows the importance of proton excitation across the Z = 28 shell gap and the role of the 2d5/2 neutron orbital. [ABSTRACT FROM AUTHOR]

We report on the spectroscopic quadrupole moment measurement of the 7/2¡" isomeric state in "JgS27 [E* = 320.5(5) keV, Tt/2 = 415(3) ns], using the time dependent perturbed angular distribution tech-nique at the RIKEN RIBF facility. Our value, | Qs |= 23(3)