Fast-timing measurements in 95,96Mo

Half-lives of the 19/2+ and 21/2+ states in 95Mo and of the 8+ and 10+ states in 96Mo were measured. Matrix elements for yrast transitions in 95Mo and 96Mo are discussed.Comment: Proceedings of XIX International School on Nuclear Physics, Neutron Physics and Applications, Varna, Bulgaria, 2011, 5 pages, 6 figure

In-beam fast-timing measurements in 103,105,107Cd

Fast-timing measurements were performed recently in the region of the medium-mass 103,105,107Cd isotopes, produced in fusion evaporation reactions. Emitted gamma-rays were detected by eight HPGe and five LaBr3:Ce detectors working in coincidence. Results on new and re-evaluated half-lives are discussed within a systematic of transition rates. The $7/2_1^+$ states in 103,105,107Cd are interpreted as arising from a single-particle excitation. The half-life analysis of the $11/2_1^-$ states in 103,105,107Cd shows no change in the single-particle transition strength as a function of the neutron number

Three-quasiparticle rotational bands in 101^{101}Rh : IBFBPM description and signature inversion of the πg9/2\pi g_{9/2} orbital

High- and intermediate-spin level structures of the 101 Rh nucleus have been studied using the reaction 70 Zn+ 36 S at 130 MeV bombarding energy. γ -rays were detected with the EUROGAM II detector array. Three new ΔI =1 rotational bands have been observed in this nucleus. The deduced level scheme is compared with results of calculations using Interacting Boson–Fermion plus Broken Pair Model. The model calculations give a consistent description of the one- and three-quasiparticle states providing fair agreement between the observed and calculated level energies and branching ratios. Experimental Routhians of the new high-spin bands and the πg 9/2 νh 11/2 bands in the neighbouring Rh and Ag nuclei have been found to exhibit signature inversion. This signature inversion can be interpreted qualitatively as the inversion of the two signatures of the proton g 9/2 orbital caused by triaxial nuclear shape with large positive γ parameter. (Elsevier

Structure of the low-lying states in (99,101,103,105)pd

The odd-mass Pd99-105 nuclei were studied via Zr90-96((12)'C-13, xn gamma) fusion/evaporation reactions. The beam was provided by the IFIN-HH Tandem accelerator at energies of approximately 50 MeV. Emitted gamma rays were detected by the hybrid multidetector system RoSphere. The structure of the low-lying excited states in Pd99-105 and their gamma-decay pattern are discussed in the framework of the rigid triaxial rotor plus particle model, providing a reasonable description of the low-lying level energies, electromagnetic transition rates, and magnetic moments

Detailed spectroscopy of quadrupole and octupole states in Yb-168

The low-lying positive-and negative-parity states in Yb-168 have been investigated by means of the (alpha, 2n gamma) fusion evaporation reaction. Using the coincidence method, the level scheme was corrected and extended up to 3MeV, for both the positive-and negative-parity states. Using the new branching ratios determined in the present experiment, the K quantum number was proposed for two negative-parity bands by direct comparison with the Alaga rule. Like in some other nuclei, one negative-parity band was established, decaying predominantly to the gamma-vibrational band. In a second experiment, the lifetimes of the low-lying excited states up to J(pi) = 6(+) in the ground-state band were measured by using the in-beam fast-timing method with the Bucharest mixed high-purity germanium (HPGe) and LaBr3:Ce detector array using the triple-gamma coincidence method. Reduced E2 transition probabilities were extracted from the measured lifetimes and compared with the corresponding observables in neighboring isotopes, showing a smooth behavior with increasing mass. The positive-and negative-parity states as well as E1 and E2 transition probability ratios revealed by these experiments are compared with the interacting boson model in the sd and spdf boson space, and with the confined beta-soft rotor model, and are found to be in good agreement