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We have calculated the strength functions of the Gamow-Teller transition processes from mirror pairs 46Ti–46Cr and 50Cr–50Fe to the odd-odd N = Z nuclei 46V and 50Mn. The calculations are carried out in fp model space with shell model diagonalization method. Calculations are compared with experimental observations. We have also discussed the effects of isospin symmetry breaking on the analogous transitions. [ABSTRACT FROM AUTHOR]

Collective rotational bands were observed for the first time in neutron-rich odd–odd 1 4 2 La by means of γ - γ - γ and γ - γ - γ - γ coincidence measurements of prompt fission γ rays from 2 5 2 Cf using multi-detector array Gammasphere. Similarity between the yrast band of 1 4 2 La and those of neighboring 1 4 4 La, 1 4 4 Ce was found and interpreted as quasiparticle excitations. PES calculations suggested triaxial deformation for the ground state of 142La. Considerable triaxial and near zero octupole deformations were deduced for the yrast band of 1 4 2 La by the TRS model calculations. The band-crossing observed in the yrast band of 1 4 2 La was interpreted to be caused by alignment of the (h 1 1 / 2 )2 proton pair, and the crossing frequency was best reproduced by the TRS calculations taking into account triaxial deformations. In contrast to the interpretations for the band crossing of 1 4 2 La, alignments of the (i 1 3 / 2 )2 neutron pair were found to be responsible for the band-crossing of the yrast band in the neighboring even-N 1 4 3 La, and triaxial degree of freedom was found to play a more significant role than octupole deformations in the nucleus, although its β 3 values deduced are large. [ABSTRACT FROM AUTHOR]

High-spin levels of Mo have been reinvestigated by analyzing the high statistics -- and --- coincidence data from the spontaneous fission of Cf taken with the Gammasphere detector array. Two bands and 30 new transitions have been identified. A potential energy surface calculation has been performed. The calculation confirmed the 3/2[411] configuration of the ground state band and 5/2[532] for the 346keV excited band, as assigned in the previous work. The two newly established bands were proposed to be one- and two-phonon vibrational bands coupling to the 5/2[532] Nilsson orbital, respectively. Triaxial projected shell model calculations have been applied to explain the level structure and are found in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

Combining the new spectroscopy results of 144Tb and previous spectroscopy studies of neighboring nuclei, a systematic investigation on the low-lying spectra in N = 78 ~ 80 isotones is performed. Good systematics have been found for the coupling patterns which couple the odd nucleon(s), such as πh11/2, vh-111/2, πh211/2, vh-211/2, to the 2+, 4+, 6+ and 3- core excitations. It is found that the relative excitation energies of the states formed by coupling h11/2 proton(s) to the 2+, 4+ core excitations are pushed up, in contrast with those formed by coupling h11/2 neutron hole(s) to the 2+, 4+ core excitations, which are pulled down. According to the systematics, the interpretation that the 17/2+ states observed in 141Sm and 143Gd are the fully aligned member of coupling the odd h11/2 neutron hole to the octupole 3- core excitation, is explored to the isotones 145Dy, 142Eu, and 144Tb. [ABSTRACT FROM AUTHOR]

The properties of proton resonances in the p and sd shells are studied with a single-particle potential generated by self-consistent-mean field calculations. Besides, we also propose to calculate the proton-nucleus interaction by a double-folding procedure with the density of the daughter nucleus represented by the result of the same mean-field model. Without raising any adjustable parameter, these calculations provide reasonable estimates for the widths of observed proton resonances in light nuclei. The mean-field-based calculation is particularly useful for the predications of the properties of resonances in light exotic nuclei and the direct proton capture reactions of astrophysics. [ABSTRACT FROM AUTHOR]

Using deformed Hartree-Fock and angular momentum projection (PHF) technique we try to understand the intrinsic structure and the systematics in the life times of K = 6+ isomers in the Hf isotopes (in 172-178Hf nuclei) and N = 104 Yb, Hf and W isotones. The band structure in 172Hf is reasonably well reproduced. The variation in the B(E2;2+ → 0+) values in the Hf isotopes as well as N = 104 isotones are well reproduced. The calculated K-forbidden E2 transition probabilities from the isomer bandheads to the 4+ yrast states qualitatively explain the variation of the lifetimes with N and Z. [ABSTRACT FROM AUTHOR]