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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 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

12 pages, 5 figures, 3 tables.-- PACS nrs.: 23.40.Hc; 27.20.+n.-- Printed version published Sep 15, 2008.-- ArXiv pre-print available at: http://arxiv.org/abs/0806.3025 ; The β-delayed charged particle emission from Li-11 has been studied with emphasis on the three-body nαHe-6 and five-body 2α3n channels from the 10.59 and 18.15 MeV states in Be-11. Monte Carlo simulations using an R-matrix formalism lead to the conclusion that the He-A resonance states play a significant role in the break-up of these states. The results exclude an earlier assumption of a phase-space description of the break-up process of the 18.15 MeV state. Evidence for extra sequential decay paths is found for both states. ; This work has been supported by the Spanish CICYT, under the projects FPA2002-04181-C04-02, FPA2005-02379 and theMEC Consolider project CSD2007-00042, the European Union Sixth Framework through RII3-EURONS (contract No. 506065) and the Swedish Knut and Alice Wallenberg Foundation. M. Madurga acknowledges the support of the Spanish MEC under the FPU program, FPU AP-2004-0002. ; Peer reviewed

Absolute branching ratios to unbound states in C12 populated in the β decays of N12 and B12 are reported. Clean sources of N12 and B12 were obtained using the isotope separation on-line (ISOL) method. The relative branching ratios to the different populated states were extracted using single-alpha as well as complete kinematics triple-alpha spectra. These two largely independent methods give consistent results. Absolute normalization is achieved via the precisely known absolute branching ratio to the bound 4.44 MeV state in C12. The extracted branching ratios to the unbound states are a factor of three more precise than previous measurements. Branching ratios in the decay of Na20 are also extracted and used to check the results. © 2009 The American Physical Society. ; Supported by the Academy of Finland (Project No. 44875), by the Spanish Agency CICYT (Nos. FPA2007–62170 and FPA2007–62216), by the European Union Sixth Framework Programme "EURONS" (No. 506065), by the Swedish Research Council, and the Knut and Alice Wallenberg foundation. ; Peer Reviewed

5 pages, 2 tables, 3 figures.--PACS nrs.: 23.40.Hc; 27.20.+n. ; The beta decay of O-13 has been studied at the IGISOL facility of the Jyvaskyla accelerator centre (Finland). By developing a low-energy isotope-separated beam of O-13 and using a modern segmented charged-particle detector array an improved measurement of the delayed proton spectrum was possible. Protons with energy up to more than 12 MeV are measured and the corresponding log(ft) values extracted. A revised decay scheme is constructed. The connection to molecular states and the shell model is discussed. ; This work was supported by the Academy of Finland under the Finnish Centre 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 FPA2002-04181-C04-02, and by the EU-RI3 (Integrated Infrastructure Initiative) under contract no 506065. ; Peer reviewed