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Two rotational hands are identified in Cs-119, one of which having very similar pattern to that of the strongly-coupled pi g(9/2)[404]9/2(+) band. The properties of the bands with similar patterns extracted from the experimental data are in agreement with a chiral interpretation. Tilted axis cranking covariant density functional theory with pairing correlations and particle-number conserving cranked shell model calculations are employed to determine the deformation and to investigate the band configurations, respectively. It results that the backbending is induced by the rotational alignment of two h(11/2 )protons, whose angular momenta reorient from the short to the intermediate axis, in a plane orthogonal to the angular momentum of the strongly-coupled g(9/2) proton which keeps aligned along the long axis. The total spin points in 3D, inducing the breaking of the chiral symmetry. This is the first observation of candidate chiral bands built on a configuration with three protons, one in the strongly coupled [404]9/2(+) orbital which does not change orientation with increasing rotational frequency, and two in the h(1)(1/)(2) orbital which reorients to the rotation axis. The bands are observed in the transient backbending regime, showing that the chirality in nuclei is a general phenomenon, being robust and present not only in nuclei with nearly maximal triaxiality and pure configurations, but also in nuclei with moderate triaxiality and mixed configurations which gradually evolve from one to three-quasiparticle configurations, like in the backbending region., QC 20220408

Fine structure in the alpha decay of U-223 was observed in the fusion-evaporation reaction Re-187(Ar-40, p3n) by using fast digital pulse processing technique. Two alpha-decay branches of U-223 feeding the ground state and 244 keV excited state of Th-219 were identified by establishing the decay chain U-223 (alpha(1)) under right arrow Th-219 (alpha(2)) under right arrow Ra-215 (alpha(3)) under right arrow Rn-211. The alpha-particle energy for the ground-state to ground-state transition of U-223 was determined to be 8993(17) keV, 213 keV higher than the previous value, the half-life was updated to be 62(-10)(+14) mu s. Evolution of nuclear structure for N = 131 even-Z isotones from Po to U was discussed in the frameworks of nuclear mass and reduced alpha-decay width, a weakening octupole deformation in the ground state of U-223 relative to its lighter isotones Ra-219 and Th-221 was suggested., QC 20200203