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In a previous work (El Bassem and Oulne (2015) [20] ), hereafter referred to as paper I, we have investigated the ground-state properties of Nd , Ce and Sm isotopes within Hartree–Fock–Bogoliubov method with SLy5 Skyrme force in which the pairing strength has been generalized with a new proposed formula. However, that formula is more appropriate for the region of Nd . In this work, we have studied the ground-state properties of both even–even and odd Mo and Ru isotopes. For this, we have used Hartree–Fock–Bogoliubov method with SLy4 Skyrme force, and a new formula of the pairing strength which is more accurate for this region of nuclei. The results have been compared with available experimental data, the results of Hartree–Fock–Bogoliubov calculations based on the D1S Gogny effective nucleon–nucleon interaction and predictions of some nuclear models such as Finite Range Droplet Model (FRDM) and Relativistic Mean Field (RMF) theory. [ABSTRACT FROM AUTHOR]

Band structures of the neutron-rich Mo- and Ru-isotopes around A ∼ 110 are investigated using the triaxial projected shell model (TPSM) approach employing multi-quasiparticle configuration space. The mass region under investigation depicts a rich variety of band structures with well developed γ - and γγ -bands, and quasiparticle excitations based on them. It is demonstrated that TPSM provides a reasonable description of most of the observed properties, in particular, detailed structure variations observed in Mo-isotopes are well reproduced in the present work. [ABSTRACT FROM AUTHOR]

Abstract: A fusion evaporation experiment, performed at the HORUS cube spectrometer at the Cologne FN-Tandem accelerator, is presented and discussed. Via the analysis of γγ coincidences, it was possible to extend the level scheme with 40 new levels and 81 decays. Several new spins and multipole mixing ratios were determined using the γγ angular correlation technique. In addition, a DSAM analysis was performed and 14 new effective lifetimes were determined in the femtosecond range. Thus, several effective transition strengths were determined. Investigating the phononic structure, candidates for the quadrupole–octupole phonon multiplet were found. The data is compared to calculations within the Interacting Boson Model (IBM-1) in the U(5) limit, the O(6) limit as well as a transitional class U(5)–O(6). The low spin level energies show characteristics of multiphonon excitations and point towards 102Ru resembling an anharmonic vibrational nucleus. The transition strengths do not exactly match this picture, and are described in a better way using the U(5)–O(6) calculation. [Copyright &y& Elsevier]

Abstract: A sample of 100MoO3 powder with molybdenum enriched in 100Mo to 99.5% and mass of 1199 g was measured for 18120 h in a low-background set-up with 4 HP Ge detectors ( volume each one) deep underground (3600 m w.e.) at the Laboratori Nazionali del Gran Sasso of the INFN (Italy). The two γ quanta of 540 keV and of 591 keV emitted in the deexcitation process after a decay of 100Mo to the excited level of 100Ru () are observed in the accumulated data both in coincidence and in the 1-dimensional sum spectrum. The measured half life is: , well in agreement with positive results obtained in previous experiments. Moreover, the limit on charge non-conserving β decay of 100Mo is also set: at 90% C.L.; it corresponds to the limit on CNC admixture in weak currents: . [ABSTRACT FROM AUTHOR]

Abstract: The coincidence detection efficiency of the TUNL-ITEP apparatus designed for measuring half-life times of two-neutrino double-beta () decay transitions to excited final states in daughter nuclei has been measured with a factor of 2.4 improved accuracy. In addition, the previous measuring time of 455 days for the study of the 100Mo decay to the first excited state in 100Ru has been increased by 450 days, and a new result (combined with the previous measurement obtained with the same apparatus) for this transition is presented: . Measured decay half-life times to excited states can be used to test the reliability of nuclear matrix element calculations needed for determining the effective neutrino mass from zero-neutrino double-beta decay data. We also present new limits for transitions to higher excited states in 100Ru which, if improved, may be of interest for more exotic conjectures, like a bosonic component to neutrino statistics. [Copyright &y& Elsevier]