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13 pags., 9 figs., 2 tabs., Excited states of In129 populated following the β decay of Cd129 were experimentally studied with the GRIFFIN spectrometer at the ISAC facility of TRIUMF, Canada. A 480-MeV proton beam was impinged on a uranium carbide target and Cd129 was extracted using the Ion Guide Laser Ion Source (IG-LIS). β and γ rays following the decay of Cd129 were detected with the GRIFFIN spectrometer comprising the plastic scintillator SCEPTAR and 16 high-purity germanium (HPGe) clover-type detectors. From the β-γ-γ coincidence analysis, 32 new transitions and seven new excited states were established, expanding the previously known level scheme of In129. The logft values deduced from the β-feeding intensities suggest that some of the high-lying states were populated by the ν0g7/2→π0g9/2 allowed Gamow-Teller (GT) transition, which indicates that the allowed GT transition is more dominant in the Cd129 decay than previously reported. Observation of fragmented Gamow-Teller strengths is consistent with theoretical calculations., The authors would like to thank the operators at the TRIUMF-ISAC facility for providing the radioactive beam. This work was partially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canada Research Chairs Program, NSERC Discovery Grants No. SAPIN-2014-00028 and No. RGPAS 462257-2014, the NSERC CREATE Program IsoSiM (Isotopes for Science and Medicine), the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P, the US National Science Foundation (NSF) under Contract No. NSF14-01574, and the Mexican DGAPA-UNAM program under Contract No. PAPIIT-IN110418. The GRIFFIN spectrometer was funded by the Canada Foundation for Innovation (CFI), TRIUMF, and the University of Guelph. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada (NRC). Y.S. would like to thank Jorge Agramunt (IFIC Valencia, Spain) for providing a program for fitting the time distribution of β particles.The authors would like to thank the operators at the TRIUMF-ISAC facility for providing the radioactive beam. This work was partially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canada Research Chairs Program, NSERC Discovery Grants No. SAPIN-2014-00028 and No. RGPAS 462257-2014, the NSERC CREATE Program IsoSiM (Isotopes for Science and Medicine), the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2017-84756-C4-2-P, the US National Science Foundation (NSF) under Contract No. NSF14-01574, and the Mexican DGAPA-UNAM program under Contract No. PAPIIT-IN110418. The GRIFFIN spectrometer was funded by the Canada Foundation for Innovation (CFI), TRIUMF, and the University of Guelph. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada (NRC). Y.S. would like to thank Jorge Agramunt (IFIC Valencia, Spain) for providing a program for fitting the time distribution of β particles.

The island of inversion for neutron-rich nuclei in the vicinity of N=20 has become the testing ground par excellence for our understanding and modeling of shell evolution with isospin. In this context, the structure of the transitional nucleus ²⁹Mg is critical. The first quantitative measurements of the single-particle structure of ²⁹Mg are reported, using data from the d(²⁸Mg, p γ)²⁹Mg reaction. Two key states carrying significant ℓ=3 (f-wave) strength were identified at 2.40±0.10 (Jπ=5/2¯) and 4.28±0.04 MeV (7/2¯). New state-of-the-art shell-model calculations have been performed and the predictions are compared in detail with the experimental results. While the two lowest 7/2¯ levels are well described, the sharing of single-particle strength disagrees with experiment for both the 3/2¯ and 5/2¯ levels and there appear to be general problems with configurations involving the p3/2 neutron orbital and core-excited components. These conclusions are supported by an analysis of the neutron occupancies in the shell-model calculations.

R. Dunlop et al. ; 6 págs.; 7 figs.; 1 tab. ; Rapid Communications, The β-decay half-lives of Cd128-130 have been measured with the newly commissioned GRIFFIN γ-ray spectrometer at the TRIUMF-ISAC facility. The time structures of the most intense γ rays emitted following the β decay were used to determine the half-lives of Cd128 and Cd130 to be T1/2=246.2(21) ms and T1/2=126(4) ms, respectively. The half-lives of the 3/2+ and 11/2- states of Cd129 were measured to be T1/2(3/2+)=157(8) ms and T1/2(11/2-)=147(3) ms. The half-lives of the Cd isotopes around the N=82 shell closure are an important ingredient in astrophysical simulations to derive the magnitude of the second r-process abundance peak in the A∼130 region. Our new results are compared with recent literature values and theoretical calculations. ©2016 American Physical Society, This work has been partially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Canada Research Chairs Program. I.D. and R.C.-F. are supported by NSERC Discovery Grants SAPIN-2014-00028 and RGPAS 462257-2014. A.J. acknowledges financial support by the Spanish Ministerio de Ciencia e Innovación under contract FPA2011-29854-C04 and the Spanish Ministerio de Economía y Competitividad under contract FPA2014- 57196-C5-4-P. S.L.T acknowledges financial support from the U.S. National Science Foundation under contract NSF- 14-01574. E.P.-R. acknowledges financial support from the DGAPA-UNAM under the PASPA program. The GRIFFIN spectrometer was funded by the Canada Foundation for Innovation, TRIUMF, and the University of Guelph. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada.