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A. Jungclaus et al. ; 6 págs.; 4 figs. ; Rapid Communications ; For the first time, the γ decay of excited states has been observed in a nucleus situated in the quadrant south-east of doubly magic Sn132, a region in which experimental information so far is limited to ground-state properties. Six γ rays with energies of 50, 86, 103, 227, 357, and 602 keV were observed following the β-delayed neutron emission from Cd85133, populated in the projectile fission of a U238 beam at the Radioactive Isotope Beam Factory at RIKEN within the EURICA project. The new experimental information is compared to the results of a modern realistic shell-model calculation, the first one in this region very far from stability, focusing in particular on the π0g9/2-1 - ν1f7/2 particle-hole multiplet in In83132. In addition, theoretical estimates based on a scaling of the two-body matrix elements for the πh11/2-1 - νg9/2 analog multiplet in Tl127208, one major proton and one major neutron shell above, are presented. ©2016 American Physical Society ; We thank the staff of the RIKEN Nishina Center accelerator complex for providing stable beams with high intensities to the experiment. We acknowledge the EUROBALL Owners Committee for the loan of germanium detectors and the PreSpec Collaboration for the readout electronics of the cluster detectors. This work was supported by the Spanish Ministerio de Ciencia e Innovación under Contract No. FPA2011-29854-C04 and the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2014-57196-C5- 4-P, the Generalitat Valenciana (Spain) under Grant No. PROMETEO/2010/101, the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. NRF-2012R1A1A1041763), the Priority Centers Research Program in Korea (2009-0093817), OTKA Contract No. K-100835, JSPS KAKENHI (Grant No. 25247045), the European Commission through the Marie Curie Actions call PEOPLE-2011FP7-IEF under Contract No. 300096 and the German BMBF (No. 05P12RDCIA and No. 05P12RDNUP), and Helmholtz International Center for FAIR. ; Peer Reviewed

J. Taprogge et al.; 11 pags.; 8 figs.; 2 tabs.; PACS number(s): 23.20.Lv, 23.40.−s, 21.60.Cs, 27.60.+j ; ©2015 American Physical Society. The β decay of 129Cd, produced in the relativistic fission of a 238U beam, was experimentally studied at the RIBF facility at the RIKEN Nishina Center. From the γ radiation emitted after the β decays, a level scheme of 129In was established comprising 31 excited states and 69 γ -ray transitions. The experimentally determined level energies are compared to state-of-the-art shell-model calculations. The half-lives of the two β-decaying states in 129Cd were deduced and the β feeding to excited states in 129In were analyzed. It is found that, as in most cases in the Z < 50, N 82 region, both decays are dominated by the ν0g7/2 → π0g9/2 Gamow–Teller transition, although the contribution of first-forbidden transitions cannot be neglected. ; This work was supported by the Spanish Ministerio de Ciencia e Innovacion under contracts FPA2009-13377-C02 and FPA2011-29854- C04, the Generalitat Valenciana (Spain) under grant PROMETEO/2010/101, the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. NRF-2012R1A1A1041763), the Priority Centers Research Program in Korea (2009-0093817), OTKA contract number K-100835, JSPS KAKENHI (Grant No. 25247045), the European Commission through the Marie Curie Actions call FP7-PEOPLE-2011-IEF under Contract No. 300096, the US Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357, the "RIKEN foreign research program," and the German BMBF (No. 05P12RDCIA and 05P12RDNUP) and HIC for FAIR. ; Peer Reviewed

J. Taprogge, et al. ; 5 pags. ; 4 figs. ; 1 tab. ; Open Access funded by SCOAP3 - Sponsoring Consortium for Open Access Publising in Particle Physics ; © 2014 The Authors. The decay of an isomeric state in the neutron-rich nucleus 129Cd has been observed via the detection of internal conversion and Compton electrons providing first experimental information on excited states in this nucleus. The isomer was populated in the projectile fission of a 238U beam at the Radioactive Isotope Beam Factory at RIKEN. From the measured yields of γ-rays and internal conversion electrons, a multipolarity of E3 was tentatively assigned to the isomeric transition. A half-life of T1/2=3.6(2)ms was determined for the new state which was assigned a spin of (21/2+), based on a comparison to shell model calculations performed using state-of-the-art realistic effective interactions. ; This work was supported by the Spanish Ministerio de Ciencia e Innovación under contracts FPA2009-13377-C02 and FPA2011-29854-C04, the Generalitat Valenciana (Spain) under grant PROMETEO/2010/101, the Japanese government under contract KAKENHI (25247045), the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. NRF-2012R1A1A1041763), the Priority Centers Research Program in Korea (2009-0093817), OTKA contract number K-100835, the European Commission through the Marie Curie Actions call FP7-PEOPLE-2011-IEF under Contract No. 300096, the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357, STFC (UK), and the German BMBF (Nos. 05P12RDCIA and 05P12RDNUP) and HIC for FAIR. ; Peer Reviewed

The β decay of the N = 83 nucleus ¹³¹Cd has been studied at the RIBF facility at the RIKEN Nishina Center. The main purpose of the study was to identify the position of the 1p₃/₂ and 0 f₅/₂ proton-hole states and the energies of core-excited configurations in the semi-magic nucleus ¹³¹In. From the radiation emitted following the ββ decay, a level scheme of ¹³¹In was established and the β feeding to each excited state determined. Similarities between the single-particle transitions observed in the ββ decays of the N = 83 isotones ¹³²In and ¹³¹Cd are discussed. Finally the excitation energies of several core-excited configurations in ¹³¹In are compared to QRPA and shell-model calculations. ; This work was supported by the Spanish Ministerio de Ciencia e Innovaci´on under contract FPA2011-29854-C04 and the Spanish Ministerio de Econom´ıa y Competitividad under contract FPA2014-57196-C5-4-P, the Generalitat Valenciana (Spain) under grant PROMETEO/2010/101, the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. NRF-2014S1A2A2028636), the Priority Centers Research Program in Korea (2009-0093817), OTKA contract number K-100835, JSPS KAKENHI (Grant No. 25247045), the Grant by IN2P3-RFBR under Agreement No. 110291054, the STFC (UK), the European Commission through the Marie Curie Actions call FP7-PEOPLE-2011- IEF under Contract No. 300096, the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02- 06CH11357, the "RIKEN foreign research program" and the German BMBF (No. 05P12RDCIA and 05P12RDNUP) and HIC for FAIR.

The β decay of the semi-magic nucleus 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 ¹³⁰In and the observation of additional β feeding to high-lying core-excited states in ¹³⁰In. 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. ; This work was supported by the Spanish Ministerio de Ciencia e Innovaci´on under contract FPA2011-29854-C04 and the Spanish Ministerio de Econom´ıa y Competitividad under Contract No. FPA2014-57196-C5- 4-P, the Generalitat Valenciana (Spain) under Grant No. PROMETEO/2010/101, the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (NRF-2014S1A2A2028636, 2016K1A3A7A09005579), the Priority Centers Research Program in Korea (2009-0093817), OTKA Contract No. K-100835, JSPS KAKENHI (Grant No. 25247045), the European Commission through the Marie Curie Actions call FP7-PEOPLE-2011-IEF under Contract No. 300096, the US Department of Energy, Office of Nuclear Physics, under Contract No.DE-AC02-06CH11357, the STFC (UK), the "RIKEN foreign research program," the German BMBF (No. 05P12RDCIA, No. 05P12RDNUP, and No. 05P12PKFNE), HIC for FAIR, the DFG cluster of excellence "Origin and Structure of the Universe," and DFG (Contract No. KR2326/2-1).