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The triple-α-particle breakup of states in the triple-α continuum of C12 has been investigated by way of coincident detection of all three α particles of the breakup. The states have been fed in the β decay of N12 and B12, and the α particles measured using a setup that covers all of the triple-α phase space. Contributions from the breakup through the Be8(0+) ground state as well as other channels-interpreted as breakup through excited energies in Be8-have been identified. Spins and parities of C12 triple-α continuum states are deduced from the measured phase-space distributions for breakup through Be8 above the ground state by comparison to a fully symmetrized sequential R-matrix description of the breakup. At around 10 MeV in C12, the breakup is found to be dominated by 0+ strength breaking up through the ghost of the Be8(0+) ground state with L=0 angular momentum between the first emitted α particle and the intermediate Be8 nucleus. For C12 energies above the 12.7 MeV 1+ state, however, L=2 breakup of a C12 2+ state through the Be8(2+) excited state dominates. Furthermore, the possibility of a 2+ excited state in the 9-12 MeV region of C12 is investigated. © 2009 The American Physical Society. ; Supported by the Academy of Finland under the Finnish Center of Excellence Programme 2000–2005 (Project No. 44875, Nuclear and Condensed Matter Physics Programme at JYFL); by the European Union Fifth Framework Programme "Improving Human Potential—Access to Research Infrastructure," Contract No. HPRI-CT-1999-00044; by the Spanish CICYT Agency under project number FPA2007-62170 and the MICINN Consolider project CSD2007-00042; and by the EU-RI3 (Integgrated Infrastructure Initiative) under Contract No. 506065. ; Peer Reviewed

We report on the observation of α decay from a state in 10B at 11.48 MeV. The only observed decay branch is to the first T=1 state in 6Li at 3.56 MeV. The apparent absence of an α-decay branch to the (T=0) ground state in 6Li suggests that the 11.48-MeV state should be assigned isospin T=1. The spin and parity of the 11.48-MeV state could not be directly determined from the present study apart from J=0 being ruled out by the observed angular correlation. We conjecture that the 11.48-MeV state is the analog of the 10.15-MeV, (4 +) state in 10Be, constitutes the third member of a rotational band built on the 0 + state at 7.65 MeV, and has pronounced molecular structure. © 2012 American Physical Society. ; Support of the Spanish CICYT research Grant No. FPA2009-07387 and the MICINN Consolider Project No. CSD 2007-00042 as well as the support of the European Union VI Framework through RII3-EURONS/JRA4-DLEP (Contract No. 506065). OSK acknowledges support from the Villum Kann Rasmussen Foundation. ; Peer Reviewed

6 pages, 1 table, 5 figures.-- El pdf del artículo es la versión pre-print.-- et al. ; The Li-9 + H-2 reaction has been investigated at 2.36 MeV/u at the REX-ISOLDE facility. In this Letter we focus on the Li-10 + p channel which potentially holds spectroscopic information on the unbound nucleus Li-10. The experimental excitation energy spectrum and angular distribution are compared with CCBA calculations. These calculations clearly support the existence of a low-lying (s) virtual state, with a (negative) scattering length of the order a(s) ~ 13-24 fm and a P-1/2 resonance with an energy of E-r ≈ 0.38 MeV and a width of Γ ≈ 0.2 MeV. ; This work has been supported by the European Union Fifth Framework under contract No. HPRI-CT-1999-00018, the BMBF under contract 06 DA 115, GSI under contract DARIC, partly by the Spanish CICYT Agency under the projects numbers FPA2005-02379 and FPA2005-04460 as well as by the ISOLDE collaboration. ; Peer reviewed

5 pags., 2 figs. -- International Symposium on Nuclear Astrophysics — Nuclei in the Cosmos — IX, June 25-30 2006, CERN, Geneva, Switzerland ; The aim of this work is to study the β-delayed multiparticle break-up of the 5/2− state in 9Be at 2.43 MeV excitation energy. This process is relevant as it has been proposed recently that this level plays a role in the α(αn,γ) 9Be reaction. This state breaks-up in 2α+n, and sequential as well as direct ("democratic") decay have previously been considered. In our work energy and direction of the two emitted α particles has been measured, while those of the neutron have been reconstructed. The sequential decay is considered using the R-matrix formalism. For the democratic decay the hyper-spherical harmonics functions are used. The different decay processes are compared with the data using the Monte-Carlo method. Our preliminary results indicate that the data is better described when democratic decay is assumed. ; This work is supported by the Spanish MEC under the project FPA2002-04181-C04-02 and the FPU program.

Riisager, Karsten et al. ; We have observed β−β−-delayed proton emission from the neutron-rich nucleus 11Be by analyzing a sample collected at the ISOLDE facility at CERN with accelerator mass spectrometry (AMS). With a branching ratio of (8.3±0.9)⋅10−6(8.3±0.9)⋅10−6 the strength of this decay mode, as measured by the BGTBGT-value, is unexpectedly high. The result is discussed within a simple single-particle model and could be interpreted as a quasi-free decay of the 11Be halo neutron into a single-proton state. ; We acknowledge support from the European Union Seventh Framework through ENSAR (contract No. 262010), from Austrian Science Fund (FWF) P22164-N20, from Spanish MINECO through projects FPA2010-17142 and FPA2012-32443, and CPAN ConsoliderCSD-2007-00042. ; Peer reviewed

The experimental study of the fusion of light neutron-rich nucleus 8He with 206Pb is reported in this work. A fusion stack of 206Pb targets has been used for this study. The most prominent evaporation residue (210Po), which has half-life of 138 days and decays by alpha emission, is populated in the reaction. Radiochemical analysis technique is used to extract the yield of this evaporation residue. © Owned by the authors, published by EDP Sciences, 2011 ; This work was partially supported by the Spanish Ministry of Science and Innovation (MICINN) under projects FPA2007-63074 (FINURA) and INGENIO-2010 (CPAN). It has also been supported by the European Union "SPIRAL2 preparatory phase" Grant agreement 212692, through the FP7 European program ; Peer Reviewed

12 páginas, 9 figuras, 3 tablas.-- et al. ; The reaction 8Li + 2H has been studied in inverse kinematics at the incident energy of 3.15 MeV/nucleon, using the REX-ISOLDE post-accelerator. The reaction channels corresponding to (d,p), (d,d), and (d,t) reactions populating ground states and low-lying excited states in 7 -9Li have been identified and the related angular distributions extracted and compared with coupled-channels, distorted-wave Born approximation (DWBA), and coupled-reaction-channels calculations. For the inelastic and (d,t) channels we find that higher order effects are very important and hence one needs to go beyond the simple DWBA to extract reliable structure information from these processes. © 2011 American Physical Society. ; The financial support of the Swedish Research Council for this work under Grant No. 2008-4158 is gratefully acknowledged, as well as support by the Lars Hierta Memorial Foundation. T. Nilsson acknowledges support through the Royal Swedish Academy of Sciences Research program by a grant from the Knut and Alice Wallenberg Foundation. This work is partially supported by the Spanish Ministerio de Ciencia e Innovacion under Projects No. FPA2006-13807- ´ C02-01, No. FPA2009-08848, No. FPA2009-07653, No. FPA2009-07387, and No. FPA2010-17142 and by the European Union Sixth Framework through RII3-EURONS (Contract No. 506065). ; Peer Reviewed

The β decays of N12 and B12 have been studied at KVI and JYFL to resolve the composition of the broad and interfering 0+ and 2 + strengths in the triple-α continuum. For the first time a complete treatment of 3α decay is presented including all major breakup channels. A multilevel, many-channel R-matrix formalism has been developed for the complete description of the breakup in combination with the recently published separate analysis of angular correlations. We find that, in addition to the Hoyle state at 7.65 MeV, more than one 0+ and 2+ state is needed to reproduce the spectra. Broad 03+ and 22+ states are found between 10.5 and 12 MeV in this work. The presence of β strength up to the N12 Q-value window suggests the presence of additional 0+ and 2 + components in the C12 structure at energies above 12.7 MeV. © 2010 The American Physical Society. ; Supported by the Academy of Finland (Project No. 44875), by the Spanish Agency CICYT (Nos. FPA2005-02379 and FPA2007-62216) and MEC Consolider Project No. CSD2007-00042, by the Belgian IAP P6/23 project and FWO-Vlaanderen, by the European Union sixth Framework Programme "EURONS"(No. 506065), and by the Swedish Research Council and the Knut and Alice Wallenberg Foundation. T.N. is a Royal Swedish Academy of Sciences Research Fellow supported by a grant from the Knut and Alice Wallenberg Foundation. The work at KVI was performed as part of Program 48 (TRIµP) of the Stichting voor Fundamenteel Onderzoek der Materie (FOM). ; Peer Reviewed

V. Pesudo et al. -- 6 pags., 10 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0 ; This work reports on the scattering of 11Be on 197Au at energies around and below the Coulomb barrier. By experimentally identifying the elastic scattering, inelastic scattering and breakup channels, and comparing them with different calculations, valuable information on the 11Be structure and its B(E1) distribution to the continuum are obtained. On top of that, a deeper understanding of the scattering process at low energies is achieved for reactions of this kind, making these studies extendable to other loosely-bound systems like 17,19C. ; This work was supported by the Spanish Government under the projects FPA2015-64969-P, FIS2014-53448-C2-1-P, FPA2013-47327-c02-01-R, FPA2012-32443, FIS2013-41994-P and Consolider CPAN CSD2007-00042; the EUROCORES project EUI-2009-04162; the European Unions Horizon 2020 research and innovation program under grant agreement No 654002; the Helmholtz Association (HGT) through the Nuclear Astrophysics Virtual Institute (VH-VI-417); ATI Sistemas; The Natural Sciences and Engineering Research Council of Canada; The Canada Foundation for Innovation; and the British Columbia Knowledge Development Fund. TRIUMF receives federal funding via a contribution agreement through the National Research Council of Canada. OSK acknowledges support from the Villum Foundation. ; Peer Reviewed

R. Lica et al. -- 6 pags., 3 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0 ; The β- decay of Mg34 was used to study the Al34 nucleus through γ spectroscopy at the Isotope Separator On-Line facility of CERN. Previous studies identified two β-decaying states in Al34 having spin-parity assignments Jπ=4- dominated by the normal configuration π(d5/2)-1 - ν(f7/2) and Jπ=1+ by the intruder configuration π(d5/2)-1 - ν(d3/2)-1(f7/2)2. Their unknown ordering and relative energy have been the subject of debate for the placement of Al34 inside or outside the N=20 >island of inversion.> We report here that the 1+ intruder lies only 46.6 keV above the 4- ground state. In addition, a new half-life of T1/2=44.9(4)ms, that is twice as long as the previously measured 20(10) ms, has been determined for Mg34. Large-scale shell-model calculations with the recently developed sdpf-u-mix interaction are compared with the new data and used to interpret the mechanisms at play at the very border of the N=20 island of inversion. ; This Rapid Communication was partially supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS-UEFISCDI Project No. PN-II-RU-TE-2014-4-1455, the Romanian IFA Grant CERN/ISOLDE, by FWO-Vlaanderen (Belgium), by GOA/2010/010 (BOF KU Leuven), and by the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12). Support from the U.K. Science and Technology Facilities Council, the European Union Seventh Framework through ENSAR (Contract No. 262010), the MINECO (Spain) Grants No. FPA2015-64969- P, No. FPA2014-57196, and No. FPA2015-65035-P, Programme "Centros de Excelencia Severo Ochoa" Program No. SEV-2012-0249, the German BMBF under Contract No. 05P15PKCIA (ISOLDE), and "Verbundprojekt 05P2015" also is acknowledged. ; Peer Reviewed

B. Olaizola et al. ; 7 págs.; 5 figs.; 1 tab. ; Open Access funded by Creative Commons Atribution Licence 3.0 ; γ-ray and fast-timing spectroscopy were used to study levels in Al30 populated following the β- decay of Mg30. Five new transitions and three new levels were located in Al30. A search was made to identify the third 1+ state expected at an excitation energy of ∼2.5 MeV. Two new levels were found, at 3163.9 and 3362.5 keV, that are firm candidates for this state. Using the advanced time-delayed (ATD) βγγ(t) method we have measured the lifetime of the 243.8-keV state to be T1/2=15(4)ps, which implies that the 243.8-keV transition is mainly of M1 character. Its fast B(M1;2+→3+) value of 0.10(3) W.u. is in very good agreement with the USD shell-model prediction of 0.090 W.u. The 1801.5-keV level is the only level observed in this study that could be a candidate for the second excited 2+ state. Published by the American Physical Society ; Fast-timing detectors and electronics were provided by the Fast Timing Collaboration. This work was supported in part by the Spanish MINECO through the FPA2013-41467-P, FPA2015-64969-P, and FPA2015-65035-P projects, Grupo de Física Nuclear (GFN) at UCM and by the NuPNET network FATIMA via the PRI-PIMNUP-2011-1338 project. Support by the European Union Sixth Framework Programme through RII3-EURONS (Contract No. 506065) is acknowledged. ; Peer Reviewed

R. Lică et al. ; 7 págs.; 5 figs.; 3 tabs. ; Open Access funded by Creative Commons Atribution Licence 3.0 ; The levels in Sn129 populated from the β- decay of In129 isomers were investigated at the ISOLDE facility of CERN using the newly commissioned ISOLDE Decay Station (IDS). The lowest 12+ state and the 32+ ground state in Sn129 are expected to have configurations dominated by the neutron s12 (l=0) and d32 (l=2) single-particle states, respectively. Consequently, these states should be connected by a somewhat slow l-forbidden M1 transition. Using fast-timing spectroscopy we have measured the half-life of the 12+ 315.3-keV state, T12= 19(10) ps, which corresponds to a moderately fast M1 transition. Shell-model calculations using the CD-Bonn effective interaction, with standard effective charges and g factors, predict a 4-ns half-life for this level. We can reconcile the shell-model calculations to the measured T12 value by the renormalization of the M1 effective operator for neutron holes. ; This work was partially supported by the Spanish MINECO through Projects No. FPA2012-32443, No. FPA2013-41267-P, and CPAN Consolider (Project No. CSD-2007-00042), and by Romanian IFA Grant CERN/ISOLDE. It was also partly funded by the NuPNET network FATIMA (PRI-PIMNUP-2011-1338), by FWO-Vlaanderen (Belgium), by GOA/2010/010 (BOF KU Leuven), and by the Interuniversity Attraction Poles Programme initiated by the Belgian Science PolicyOffice (BriX network P7/12). Support from Grupo de Física Nuclear (GFN-UCM), Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale (PRIN) Grant No. 2001024324 01302, German BMBF under Contracts No. 05P12PKFNE and No. 05P15PKCIA, the U.K. Science and Technology Facilities Council, and the European Union Seventh Framework through ENSAR (Contract No. 262010) is also acknowledged. Fasttiming electronics were provided by the Fast Timing Collaboration, the ISOLDE Decay Station collaboration, and MASTICON. ; Peer Reviewed

The reaction 3He+11B→d+12C* has been used to populate resonances in C12 up to an excitation energy of 15 MeV. The subsequent breakup to three α particles has been measured in complete kinematics. Dalitz plots are used to visualize and analyze the data. The Dalitz plot intensity distribution exhibits zero points characteristic of the total spin and parity of the 3α system allowing us to determine the spin and parity of a state in C12 at 13.35 MeV whose quantum numbers were hitherto not well established. The Dalitz plot intensity distributions of the 2- state at 11.83 MeV and the 1 + state at 12.71 MeV are compared with the predictions of a recent three-body calculation as well as with simpler models. All are able to reproduce the gross structures seen in the Dalitz plot, but none give an accurate description of the detailed profile of the distributions. © 2010 The American Physical Society. ; support of the Spanish CICYT research grant FPA2007-62170 and the MICINN Consolider Project CSD 2007-00042 as well as the support of the European Union VI Framework through RII3-EURONS/JRA4-DLEP (Contract No. 506065) ; Peer Reviewed

5 pags., 2 figs. -- International Symposium on Nuclear Astrophysics - Nuclei in the Cosmos - IX 25-30 June 2006 CERN ; We have studied 12C in full kinematics via the 10B( 3He,pααα) reaction at 2.45 MeV. In our data we have identified states in 12C from the ground state up to about 18 MeV, with spins ranging from 0 to 4. Due to the very good resolution, we are able to determine properties of these 12C resonances, such as their energy, width, and spin. In this contribution preliminary results from the ongoing analysis is presented. ; This work has been made possible by the CSIC I3P program, and is supported by the European Union under the Sixth framework project EURONS-contract number 506065. ; Peer reviewed

13 pags., 6 figs. 3 tabs.-- Open Access funded by Creative Commons Atribution Licence 3.0 ; The bound states of Be have been studied by removing single neutrons from Be nuclei. A 2.8 MeV u beam of Be was produced at ISOLDE, CERN and directed on to both proton and deuteron targets inducing one-neutron removal reactions. Charged particles were detected to identify the two reaction channels (d, t) and (p, d), and the individual states in Be were identified by gamma detection. All bound states but one were populated and identified in the (d, t) reaction. The combination of REX-ISOLDE and MINIBALL allowed for a clean separation of the high-lying states in Be. This is the first time these states have been separated in a reaction experiment. Differential cross sections have been calculated for all the reaction channels and compared to DWBA calculations. Spectroscopic factors are derived and compared to values from the litterature. While the overall agreement between the spectrocopic factors is poor, the ratio between the ground state and the first excited state is in agreement with the previous measured ones. Furthermore, a significant population of the state is observed, which which may indicate the presence of multi-step processes at our beam energy. ; This work was supported by the Danish Research Council, by the European Union Seventh Framework through ENSAR (Contract No. 262010) and a Marie Curie Actions Grant under Contract No. PIEF-GA-2008-219175, by the BMBF under Contracts No. 06MT7178, No. 06MT9156, No. 05P09PKCI5, No. 05P12PKFNE, No. 06DA9036I, No. 05P12RDCIA, No. 05P15PKCIA and Verbundprojekt 05P2015, by the Spanish MINNECO under Contracts No. FPA2012-34332 and No. FPA2015-, by the FWO-Vlaanderen (Belgium), by GOA/10/010 (BOF KU Leuven), by the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12), by the United Kingdom Science and Technology Facilities Council, and by Maier-Leibnitz-Laboratorium, Garching. ; Peer Reviewed