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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

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

Pragati et al. ; 8 págs.; 9 figs.; 2 tabs. ; Open Access funded by Creative Commons Atribution Licence 3.0 ; γ rays following the EC/β+ and α decay of the N = 126, Fr213 nucleus have been observed at the CERN isotope separator on-line (ISOLDE) facility with the help of γ-ray and conversion-electron spectroscopy. These γ rays establish several hitherto unknown excited states in Rn213. Also, five new α-decay branches from the Fr213 ground state have been discovered. Shell model calculations have been performed to understand the newly observed states in Rn213. Published by the American Physical Society ; Financial support from the European Union Sixth Framework through RII3-EURONS Contract No. 506065, the UK STFC, the Spanish MINECO through Grants No. FPA2005-03993, No. FPA2013-41267-P, No. FPA2014-52823-C2-1-P, and No. FPA2015-65035-P, and the Centro de Excelencia Severo Ochoa del IFIC SEV-2014-0398 Projects is gratefully acknowledged. Pragati acknowledges financial support from the Ministry of Human Resource Development, Government of India. ; 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

G. T. Koldste et al. ; 10 pags. ; 14 figs. ; 4 tabs. ; PACS number(s): 23.40.Hc, 27.30.+t ; A multihit capacity setup was used to study the decay of the dripline nucleus 31Ar, produced at the ISOLDE facility at CERN. A spectroscopic analysis of the β-delayed three-proton decay of 31Ar is presented for the first time together with a quantitative analysis of the β-delayed 2pγ decay. A new method for determination of the spin of low-lying levels in the βp daughter 30S using proton-proton angular correlations is presented and used to determine that the spin of the 5.2-MeV level is most likely 3+ with 4+ also possible. The half-life of 31Ar is found to be 15.1(3) ms. An improved analysis of the Fermi β strength including the β3p-decay mode gives a total measured branching ratio of 3.60(44)%, which is lower than the theoretical value found to be 4.24(43)%. Finally, a previously unidentified γ transition from the isobaric analog state in the decay of 33Ar has been found. © 2014 American Physical Society. ; This work was supported by the European Union Seventh Framework through ENSAR (Contract No. 262010). This work was partly supported by the Spanish Funding Agency under Projects No. FPA2009-07387, No. FPA2010-17142, and No. AIC-D-2011- 0684, by the French ANR (Contract No. ANR-06-BLAN- 0320). ; Peer Reviewed

The low-energy structure of 65Fe has been studied by means of γ and fast-timing spectroscopy at the ISOLDE facility, CERN. A level scheme of 65Fe populated following the β-decay of 65Mn was established for the first time. It includes 41 levels and 85 transitions. The excitation energy of the β-decaying isomer in 65Fe has been precisely determined at 393.7(2) keV. The β-delayed neutron emission branch was measured as Pn = 7.9(12)%, which cannot be reconciled with the previously reported value of 21.0(5)%. Four γ rays and four excited states in 64Fe were identified as being populated following the β-n decay. Four lifetimes and five lifetime limits in the subnanosecond range have been measured using the advanced time-delayed βγγ(t) method. The level scheme is compared with shell-model calculations. Tentative spin and parity assignments are proposed based on the observed transition rates, the calculations, and the systematics of the region. © 2013 American Physical Society. ; This work was supported by the Spanish MINECO (FPA2010-17142 and FPA2011-29854), CPAN (CSD-2007- 00042@ Ingenio 2010), RA-NET NuPNET (PRI-PIMNUP- 2011-1338 and PRI-PIMMNUP-2011-1361) and Comunidad de Madrid, Spain (HEPHACOS S2009/ESP-1473). Support by Grupo de F´ısica Nuclear (GFN-UCM) and by the European Union Seventh Framework through ENSAR (Contract No. 262010) is also acknowledged. ; 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

9 pags., 8 figs., 4 tabs. ; The low-energy structure of Co65 was studied by means of γ-and fast-timing spectroscopy at the ISOLDE/CERN facility. The known level scheme of Co65 populated following the β-decay of Fe65 was expanded. The experimental results were compared with large-scale shell-model calculations. The measured long lifetime of the (1/21-) level confirms its nature as a highly collective state with proton excitations across the Z=28 gap and neutrons across the N=40 subshell. ; This work was partially supported by the Spanish MINECO through Projects No. FPA2014-57196 and No. FPA2015-65035-P and Centro de Excelencia Severo Ochoa Programme (Project No. SEV-2016-0597). Support by Grupo de Física Nuclear (GFN-UCM) and by the European Union Seventh Framework through ENSAR (Contract No. 262010) is also acknowledged. B.O. acknowledges funding by the CPAN project. S.R.L. acknowledges funding by the U.S. National Science Foundation under Contract No. PHY-07- 58100.

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

6 pags., 6 figs. -- 27th International Nuclear Physics Conference (INPC2019) 29 July - 2 August 2019, Glasgow, UK ; The main goal of this work is to study the structure of the highest energy states in 8Be populated following the ß+-decay and the electron capture (EC) of 8B. With this aim, two experiments were performed at ISOLDE-CERN in 2017 and 2018. The first experiment had the aim to resolve the 2+ doublet at 16.6 and 16.9 MeV, in order to study their isospin mixing. The second experiment aimed to determine a value or give an experimental upper limit to the branching ratio of the exotic EC-p decay. In this paper, we present the experimental setups and we discuss the analysis and present the preliminary results obtained so far. ; Work partially supported by the Spanish research grant FPA2015-64969-P and FPA2017-87568- P (MINECO) and the grant ENSAR2 from the H2020 program of the European Union under grant agreement No 654002.

7 pags., 9 figs., 1 tab. ; The Gamow-Teller strength distribution of the decay of Hg into Au has been determined for the first time using the total absorption gamma spectroscopy technique and has been compared with theoretical QRPA calculations using the SLy4 Skyrme force. The measured Gamow-Teller strength distribution and the half-life are described by mixing oblate and prolate configurations independently in the parent and daughter nuclei. In this theoretical framework the best description of the experimental beta strength is obtained with dominantly prolate components for both parent Hg and daughter Au. The approach also allowed us to determine an upper limit of the oblate component in the parent state. The complexity of the analysis required the development of a new approach in the analysis of the X-ray gated total absorption spectrum. ; This work was supported by Spanish Ministerio de Economía y Competitividad under grants FPA2011-24553, FPA2014-52823-C2-1-P, FPA2017-83946-C2-1-P, FPA2017-87568-P, Ministerio de Ciencia e Innovación grants PID2019-104714GB-C21 and RTI2018-098868-B-100, program Severo Ochoa (SEV-2014-0398), ENSAR (grant 262010) and by the European Union Horizon 2020 research and innovation programme under Grant Agreement No. 654002. S.E.A.O. thanks the support of CPAN Consolider-Ingenio 2010 Programme CSD2007-00042 grant. E.G. acknowledges support from TÜBITAK 2219 Abroad Research Fellowship Programme. R.B.C. acknowledges support by the Max-Planck-Partner group. Support from the technical staff and engineers of ISOLDE-CERN is acknowl- edged. W.G. acknowledges the support of STFC (UK) council grant ST/P005314/1. V.G. acknowledges the support of the National Science Center, Poland, under Contract No. 2019/35/D/ST2/02081. This work was also supported by the National Research, Development and Innovation Fund of Hungary, financed under the K18 funding scheme with Projects No. K 128729 and NN128072. P.S. acknowledges support from MCI/AEI/FEDER, UE (Spain) under grant PGC2018-093636-B-I00

10 pags.; 11 figs.; 2 tabs.; PACS number(s): 23.40.Hc, 29.30.Kv, 27.50.+e, 21.10.Pc; Open Access funded by Creative Commons Atribution Licence 3.0 ; The beta decay of the N = Z nucleus Kr-72 has been studied with the total absorption spectroscopy technique at ISOLDE (CERN). A total B(GT) = 0.79(4)g(A)(2)/4 pi has been found up to an excitation energy of 2.7 MeV. The B(GT) distribution obtained is compared with predictions from state-of-the-art theoretical calculations to learn about the ground state deformation of Kr-72. Although a dominant oblate deformation is suggested by direct comparison with quasiparticle random phase approximation (QRPA) calculations, beyond-mean-field and shell-model calculations favor a large oblate-prolate mixing in the ground state. Published by the American Physical Society ; J.A.B. acknowledges the predoctoral grant BES-2008-009412 associated with the research project FPA2007-62170 funded by Ministerio de Ciencia e Innovacion (Spain). This work has ´ been partly supported by the Spanish Ministerio de Economía y Competitividad (MINECO) through projects FPA2012- 32443, FPA2011-24553, FPA2011-29854-C04-01, FPA2013- 41267-P, FPA2014-52823-C2-1-P and FIS2011-23565, by STFC-UK (Grant No. ST/F012012/1) and by the European Union by means of the European Commission within its Seventh Framework Programme (FP7) via ENSAR (Contract No. 262010) ; Peer Reviewed

5 pags. ; 7 figs. ; Open Access funded by SCOAP3 - Sponsoring Consortium for Open Access Publishing in Particle Physics ; © 2014 The Authors. We present for the first time precise spectroscopic information on the recently discovered decay mode β-delayed 3p-emission. The detection of the 3p events gives an increased sensitivity to the high energy part of the Gamow-Teller strength distribution from the decay of 31Ar revealing that as much as 30% of the strength resides in the β3p-decay mode. A simplified description of how the main decay modes evolve as the excitation energy increases in 31Cl is provided. ; This work was supported by the European Union Seventh Framework through ENSAR (Contract No. 262010), it was partly supported by the Spanish Funding Agency under Projects No. FPA2012-32443, No. FPA2010-17142, CPAN ConsoliderCSD-2007-00042, and No. AIC-D-2011-0684. ; 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