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Search for low-spin signature inversion in the πi13/2 ⊗ νi13/2 bands in odd-odd 182,184,186Au has been conducted through the standard in-beam γ-spectroscopy techniques. The experiments for 182Au and 186Au have been performed in the Japan Atomic Energy Agency (JAEA) via the 152Sm(35Cl,5n)182Au and 172Yb(19F,5n)186Au reactions, respectively. A study of 184Au has been made using a multi-detector array GASP in LNL, Italy, via the 159Tb(29Si,4n)184Au reaction. The πi13/2 ⊗ νi13/2 bands in these three nuclei have been identified and extended up to high-spin states. In particular, the inter-band connection between the πi13/2 ⊗ νi13/2 band and the ground-state band in 184Au has been established, leading to a firm spin-and-parity assignment for the πi13/2 ⊗ νi13/2 band. The low-spin signature inversion is found in the πi13/2 ⊗ νi13/2 bands in 182,184,186Au according to our spin-assignment and the signature crossing observed at high-spin states. [ABSTRACT FROM AUTHOR]

Excited states in 188Tl have been studied experimentally using the 157Gd (35Cl, 4n) reaction at a beam energy of 170MeV. A rotational band built on the π h 9/2 ⊗ ν i 13/2 configuration with oblate deformation has been established for 188Tl. Based on the structure systematics of the oblate π h 9/2 ⊗ ν i 13/2 bands in the heavier odd-odd Tl nuclei, we have tentatively proposed spin values for the new band in 188Tl. The π h 9/2 ⊗ ν i 13/2 oblate band in 188Tl shows low-spin signature inversion, and it can be interpreted qualitatively by the two-quasiparticle plus rotor model including a J-dependent p- n residual interaction. [ABSTRACT FROM AUTHOR]

Coulomb excitation experiments were performed with 96Mo, 98Mo and 100Mo isotopes using both beam and target excitation. As a result, quadrupole deformation parameters were deduced for two lowest-lying (ground and excited) 0+ states. Surprising shape changes of these states were observed. [ABSTRACT FROM AUTHOR]

High-spin states in 169Re were studied and resulted in the identification of a strongly coupled band based on the 9/2- [514] Nilsson state and a decoupled band built on the h9/2 1/2- [541] intruder proton orbit. The cranked-shell-model calculations present configuration-dependent deformations that can explain the different band crossing frequencies. The 9/2- [514] band in 169Re shows the largest signature splitting at low spin among the known odd-mass Re isotopes. After the alignment of a pair of i13/2 neutrons, the phase of the splitting is inverted with a significantly reduced amplitude. For the 9/2- [514] bands in light odd-A Re isotopes, the signature splitting of the Routhians and its relation with the signature dependence of M1 transition matrix elements are investigated in connection with the deviation of nuclear shape from axial symmetry, suggesting an appreciable negative γ deformation for the very neutron-deficient odd-A Re isotopes. Additionally, a three-quasipariticle band was observed and assigned to be built likely on the &pie;9/2-[514] ® AE configuration. [ABSTRACT FROM AUTHOR]

A Coulomb excitation experiment was carried out with a 66Zn beam bombarding a matPb target. Four E2 matrix elements and the quadrupole moment of the 2+1 state were derived with the least-squares search code GOSIA. According to the B(E2) values, the ground band can be interpreted as a quasirotational band. It was found that the 2+1 level has a positive quadrupole moment, which may be interpreted as a soft triaxial deformation. [ABSTRACT FROM AUTHOR]

: Excited states in 187Re populated by inelastic scattering of a 500 MeV 82Se beam have been studied by means of in-beam γ-ray spectroscopy. Levels built on the 5/2+[402] and 9/2-[514] one-quasiparticle states were measured up to Iπ = (21/2+) and (21/2-), respectively. In addition, several new levels including an isomer at 1682 keV with a half-life of 114(23) ns have been found. Quasiparticle configurations of the levels and the transition rates are discussed. [ABSTRACT FROM AUTHOR]