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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

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

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

The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0 + state in C12, commonly known as the Hoyle state, proceeds sequentially via the ground state of Be8. This assumption is challenged by the recent identification of two direct α-decay branches with a combined branching ratio of 17(5)%. If correct, this would imply a corresponding reduction in the triple-α reaction rate with important astrophysical consequences. We have used the B11(He3,d) reaction to populate the Hoyle state and measured the decay to three α particles in complete kinematics. We find no evidence for direct α-decay branches, and hence our data do not support a revision of the triple-α reaction rate. We obtain an upper limit of 5×10 -3 on the direct α decay of the Hoyle state at 95% C.L., which is 1 order of magnitude better than a previous upper limit. © 2012 American Physical Society. ; Support of the Spanish CICYT Research Grants No. FPA2009-07387 and No. FPA2010-17142 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). O. S. K. acknowledges support from the Villum Kann Rasmussen Foundation. ; Peer Reviewed

5 pages, 1 table, 3 figures.-- PACS nrs.: 23.40.Hc; 27.20.+n; 21.10.Hw.-- Printed version published Jun 29, 2009.-- ArXiv available at: http://arxiv.org/abs/0904.4212v1 ; Coincidences between charged particles emitted in the β-decay of 11Li were observed using highly segmented detectors. The breakup channels involving three particles were studied in full kinematics allowing for the reconstruction of the excitation energy of the 11Be states participating in the decay. In particular, the contribution of a previously unobserved state at 16.3 MeV in 11Be has been identified selecting the α + 7He → α + 6He + n channel. The angular correlations between the α particle and the center of mass of the 6He + n system favors spin and parity assignment of 3/2− for this state as well as for the previously known state at 18 MeV. ; This work has been supported by the Spanish Ministerio de Ciencia e Innovación (MICINN), under the projects FPA2007-62170 and CSD2007-00042, the European Union Sixth Framework through RII3-EURONS (contract No. 506065) and the Swedish Knut and Alice Wallenberg Foundation. ; Peer reviewed

We have used the 10B(3He,p¿¿¿) reaction at 4.9 MeV and the 11B(3He,d¿¿¿) reaction at 8.5 MeV to determine the energy, width, and decay mechanism of resonances in 12C above the triple-¿ threshold up to 21 MeV in excitation energy. Comparison with various models has allowed us to estimate the degree of clustering of the states studied. © 2012 American Physical Society. ; Support by the Spanish Research Grant FPA2009-07387 and Consolider Project CSD2007-00042, by the European Union Sixth Framework through RII3- EURONS/ JRA4-DLEP (Contract No. 506065). Support of the CSIC I3P program cofinanced by the European Social Fund, and the support of the US Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357. O.S.K. Support from the Villum Kann Rasmussen Foundation. ; Peer Reviewed

6 pags., 4 figs., 2 tabs. -- PACS:27.20.+n25.55.Hp23.20.-g29.85.-c ; The reactions 10B (3He, p α α α) at 4.9 MeV and 11B (3He, d α α α) at 8.5 MeV have been used to investigate the γ decay of states in 12C. By measuring the four-body final state in complete kinematics we are able to detect γ transitions indirectly. We find γ transitions from the 15.11 MeV state in 12C to the 12.71, 11.83, 10.3 and 7.65 MeV states followed by their breakup into three α particles. The relative γ-ray branching ratios obtained are (1.2 ± 0.3), (0.32 ± 0.12), (1.4 ± 0.2) and (4.4 ± 0.8) %, respectively, with the remaining (92.7 ± 1.0) % of the γ decays going to the bound states. We obtain Γα / Γ = (2.8 ± 1.2) % for the isospin-forbidden α decay of the 15.11 MeV state. From the 12.71 MeV state we find γ transitions to the 10.3 and 7.65 MeV states. The relative γ-ray branching ratios are (0.9- 0.5 + 0.6) and (2.6- 1.2 + 1.6) %, respectively, with the remaining (96.6- 1.3 + 1.7) % of the γ decays going to the bound states. Finally, we discuss the relation between the β decay of 12N and 12B to states in 12C and the γ decay of the 15.11 MeV analog in 12C to the same states. © 2009 Elsevier B.V. ; We would like to acknowledge the 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 number 506065). D.G. is a Juan de la Cierva fellow.