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The β + /EC decay of mass separated samples of 181 Hg was studied employing the TATRA spectrometer at the ISOLDE facility at CERN. The decay scheme was constructed for the first time. A Broad Energy Germanium detector was used to achieve this by combination of high-gain γ -ray singles spectroscopy and γ – γ coincidences. The systematics of excited states associated with the 1 h 11 / 2 proton-hole configuration in odd-Au isotopes was extended. [ABSTRACT FROM AUTHOR]

A signal of isospin-asymmetric phase transition in the evolution of chemical potential is observed in hot quasi-projectiles produced in the reactions 40,48Ca + 27Al confirming an analogous observation in the lighter quasi-projectiles observed in the reaction 28Si + 112,124Sn.1 With increasing mass, the properties of hot quasi-projectiles become increasingly influenced by secondary emission. Thermodynamical observables exhibit no sensitivity to a different number of missing neutrons in the two reactions 40,48Ca + 27Al and provide a signal of dynamical emission of neutrons, which can be related to a very neutron-rich low-density region (neck) between the projectile and target. [ABSTRACT FROM AUTHOR]

Velocity distributions and production cross sections of evaporation residues have been measured in the reactionNe+Pb at projectile energies of 8.6, 11.4, 14.9 A.MeV. Essential deviations from statistical model of deexcitation have been observed. Monte Carlo simulations involving emission of non-equilibrium particles have been used in order to reproduce experimental velocity, charge and mass distributions of evaporation residues and to estimate indirectly multiplicities of pre-equilibrium particles. [ABSTRACT FROM AUTHOR]

The Operator Expansion Method (OEM) for the calculation of two-neutrino double beta decay (2 ν2 β-decay) is reconsidered. The assumed two-body Hamiltonian, in contrast to the ones considered previously, allows a consistent derivation of the OEM transition operators. The OEM is combined with the renormalized proton-neutron QRPA (pn-RQRPA) ground state wave functions and the 2 ν2 β-decay of76Ge is calculated. The influence and relative importance of the central, tensor and Coulomb interactions are investigated. We have found that the strong suppression of the nuclear matrix element M GT has its origin in the choice of the pn-RQRPA ground state wave functions of the initial and final nuclei. [ABSTRACT FROM AUTHOR]