Abstract: We construct all SUL(3) x SUR(3) chirally invariant anomalous magnetic, i.e., involving a Pauli tensor and one-derivative, interactions of one chiral [(8, 1) circle plus (1, 8)] meson fieldwith chiral [(6, 3) circle plus (3, 6)], [(3, (3) over bar) circle plus ((3) over bar), 3], and [(8, 1) circle plus (1, 8)] baryon fields and their “mirror” images. We find strong chiral selection rules; e. g., there is only one off-diagonal chirally symmetric anomalous magnetic interaction between J = 1/2 fields belonging to the [(6, 3) circle plus (3, 6)] and the [(3, (3) over bar) circle plus ((3) over bar), 3] chiral multiplets. We also study the chiral selection rules for the anomalous magnetic interactions of the [(3, (3) over bar) circle plus ((3) over bar), 3] and the [(8, 1) circle plus (1, 8)] baryon fields. Again, no diagonal and only one off-diagonal chiral SUL(3) x SUR(3) interaction of this type is allowed, that turns out also to conserve the U-A(1) symmetry. We calculate the F/D ratios for the baryons' anomalous magnetic moments predicted by these interactions in the SU(3) symmetry limit and find that only the [(6, 3) circle plus (3, 6)]-[(3, (3) over bar) circle plus ((3) over bar), 3] one reproduces F/D = 1/3, in close proximity to the value extracted from experiment.

Abstract: The beta decay of Cd-129, produced in the relativistic fission of a U-238 beam, was experimentally studied at the RIBF facility at the RIKEN Nishina Center. From the gamma radiation emitted after the beta decays, a level scheme of In-129 was established comprising 31 excited states and 69 gamma-ray transitions. The experimentally determined level energies are compared to state-of-the-art shell-model calculations. The half-lives of the two beta-decaying states in Cd-129 were deduced and the beta feeding to excited states in In-129 were analyzed. It is found that, as in most cases in the Z < 50, N <= 82 region, both decays are dominated by the nu 0g(7/2) -> pi 0g(9/2) Gamow-Teller transition, although the contribution of first-forbidden transitions cannot be neglected.

Abstract: The beta decay of the semi-magic nucleus Cd-130 has been studied at the RIBF facility at the RIKEN Nishina Center. The high statistics of the present experiment allowed for a revision of the established level scheme of In-130 and the observation of additional beta feeding to high- lying core-excited states in In-130. The experimental results are compared to shell-model calculations employing a model space consisting of the full major N = 50-82 neutron and Z = 28-50 proton shells and the NA-14 interaction, and good agreement is found.

Abstract: We report here the results of a study of the beta decay of the proton-rich Ge isotopes, Ge-60 and Ge-62, produced in an experiment at the RIKEN Nishina Center. We have improved our knowledge of the half-lives of Ge-62 [73.5(1) ms] and Ge-60 [25.0(3) ms] and its daughter nucleus, Ga-60 [69.4(2) ms]. We measured individual beta-delayed proton and gamma emissions and their related branching ratios. Decay schemes and absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. A total beta-delayed proton-emission branching ratio of 67(3)% has been obtained for Ge-60. New information has been obtained on the energy levels populated in Ga-60 and on the 1/2(-) excited state in the beta p daughter Zn-59. We extracted a ground state-to-ground state feeding of 85.3(3)% for the decay of Ge-62. Eight new y lines have been added to the deexcitation of levels populated in the Ga-62 daughter.

Abstract: Background: There have been measurements on roughly 230 nuclei that are beta-delayed neutron emitters. They range from He-8 up to La-150. Apart from 210Tl, with a branching ratio of only 0.007%, no other neutron emitter has been measured beyond A = 150. Therefore, new data are needed, particularly in the region of heavy nuclei around N = 126, in order to guide theoretical models and help understand the formation of the third r-process peak at A similar to 195. Purpose: To measure both beta-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb, and Bi isotopes beyond N = 126. Method: Ions of interest were produced by fragmentation of a U-238 beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) was used to measure ion implants and beta decays. An array of 30 He-3 tubes embedded in a polyethylene matrix (BELEN) was used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time correlations. The latter were analyzed with an analytical model and results for the half-lives and neutron-branching ratios were derived by using the binned maximum-likelihood method. Results: Twenty new beta-decay half-lives are reported for Au204-206, Hg208-211, Tl211-216, Pb215-218, and Bi218-220, nine of them for the first time. Neutron emission probabilities are reported for Hg-210,Hg-211 and Tl211-216. Conclusions: The new beta-decay half-lives are in good agreement with previous measurements on nuclei in this region. The measured neutron emission probabilities are comparable to or smaller than values predicted by global models such as relativistic Hartree Bogoliubov plus the relativistic quasi-particle random phase approximation (RHB + RQRPA).