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V. Vedía et al. -- 13 pags., 10 figs., 3 tabs. ; The existence of two close-lying nuclear states in Ga73 has recently been experimentally determined: a 1/2- spin-parity for the ground state was measured in a laser spectroscopy experiment, while a Jπ=3/2- level was observed in transfer reactions. This scenario is supported by Coulomb excitation studies, which set a limit for the energy splitting of 0.8 keV. In this work, we report on the study of the excited structure of Ga73 populated in the β decay of Zn73 produced at ISOLDE, CERN. Using β-gated, γ-ray singles, and γ-γ coincidences, we have searched for energy differences to try to delimit the ground-state energy splitting, providing a more stringent energy difference limit. Three new half-lives of excited states in Ga73 have been measured using the fast-timing method with LaBr3(Ce) detectors. From our study, we help clarify the excited structure of Ga73 and we extend the existing Zn73 decay to Ga73 with 8 new energy levels and 35 γ transitions. We observe a 195-keV transition consistent with a γ ray de-exciting a short-lived state in the β-decay parent Zn73. ; This work was partially supported by the Spanish Ministerio de economía y competitividad (MINECO) via Project No. FPA2015-65035-P, by Grupo de Física Nuclear (GFN) at Universidad Complutense de Madrid (UCM). V.V. acknowledges funding from MINECO through FPI Grant No. BES-2014-068222 and J.A.B. acknowledges the Spanish MINECO through Project No. FPA2012-32443. We recognize the support from the European Union Seventh Framework Programme through ENSAR (Contract No. 262010), and the German Bundesministerium für Bildung und Forschung (BMBF) under Grant No. 05P15PKCIA. . ; Peer Reviewed

B. Olaizola et al. -- 6 pags., 6 figs., 2 tabs. ; The lifetime of the 03+ state in Ni66, two neutrons below the N=40 subshell gap, has been measured. The transition B(E2;03+→21+) is one of the most hindered E2 transitions in the Ni isotopic chain and it implies that, unlike Ni68, there is a spherical structure at low excitation energy. We have performed extensive shell-model calculations that correctly predict this result, obtaining a spherical 0+ state at the correct energy and with an extremely low B(E2;03+→21+) value. ; This work was partially supported by the Spanish MINECO through projects FPA2013-41267-P, FPA2014- 57196, FPA2015-65035-P, and the NuPNET network FATIMA (PRI-PIMNUP-2011-1338). The support by the European Union Seventh Framework through ENSAR (Contract No. 262010) is acknowledged. Fast timing electronics were provided by the Fast Timing Collaboration and MASTICON. B.O. acknowledges funding by the CPAN project (CSD-2007-00042@ Ingenio 2010). A.A. and S.R.L. acknowledge funding by the US National Science Foundation under Contract No. PHY-07-58100. J.A.B. acknowledges funding by the Spanish MINECO through Project FPA2012-32443. A.P. is partly funded by Programme "Centros de Excelencia Severo Ochoa" (SEV-2012-0249). ; 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

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

The 9Li + 2H reaction has been investigated at 2.36 MeV/u at the REX-ISOLDE facility. In this Letter we focus on the 10Li + p channel which potentially holds spectroscopic information on the unbound nucleus 10Li. 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 as ∼ 13 - 24 fm and a p1 / 2 resonance with an energy of Er ≃ 0.38 MeV and a width of Γ ≃ 0.2 MeV. ; European Union Fifth Framework HPRI-CT-1999-00018 ; Comisión Interministerial de Investigaciones Científicas FPA2005-02379 y FPA2005-04460

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 ; 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 Física Nuclear (GFN-UCM) and by the European Union Seventh Framework through ENSAR (Contract No. 262010) is also acknowledged. Fast timing electronics were provided by the Fast Timing Collaboration and MASTICON. B.O. acknowledges funding by the CPAN (CSD-2007- 00042@ Ingenio 2010) project. A.A. and S.R.L. acknowledge funding by the US NSF under Contract No. PHY-07-58100.

The β decay of the N=Z nucleus Kr72 has been studied with the total absorption spectroscopy technique at ISOLDE (CERN). A total B(GT)=0.79(4)gA2/4π 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 Kr72. 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 ; 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)

12 pags., 8 figs., 1 tab. ; The structure of Ge80 has been investigated at the ISOLDE facility at CERN. A previous study reported for the first time a low-lying 02+ intruder state at 639 keV, based on the coincidence with a previously unobserved 1764-keV γ ray, and suggested it as evidence for shape coexistence in Ge80. We used the β decay from the 3- 22.4-keV state in Ga80 to enhance the population of low-spin states in Ge80, including any excited 0+ level, and γγ coincidences to investigate it. We observed a 1764-keV γ ray in coincidence with strong transitions in Ge80, thus not feeding the proposed 639-keV 02+. No connecting transitions from previously known levels to the 639-keV and 2403-keV 23+ states could be established either. Shell-model calculations for Ge isotopes and N=48 isotones were performed. They succeed to explain most of the experimental levels, but fail to reproduce the presence of a 02+ state below ≈1200 keV in Ge80. Our experimental findings and shell-model calculations are difficult to reconcile with a very low-lying 02+ state in Ge80. ; This work was supported by Spanish national projects FPA2015-65035-P, RTI2018-098868-B-I00, and PID2019- 104390GB-I00, by Grupo de Física Nuclear (GFN) at Universidad Complutense (Spain), by the U.S. DoE Grant No. DE-FG02-94ER40834, and by the German BMBF Grant 05P19PKFNA. The support by the European Union Seventh Framework through ENSAR (Contract No. 262010) and by the ISOLDE Collaboration and technical teams is acknowledged. ; Peer reviewed

13 pags., 5 figs., 2 tabs. ; The structure of Po208 populated through the EC/β+ decay of At208 is investigated using γ-ray spectroscopy at the ISOLDE Decay Station. The presented level scheme contains 27 new excited states and 43 new transitions, as well as a further 50 previously observed γ rays which have been (re)assigned a position. The level scheme is compared to shell model calculations. Through this analysis approximately half of the β-decay strength of At208 is found to proceed via allowed decay and half via first-forbidden decay. The first-forbidden transitions predominantly populate core excited states at high excitation energies, which is qualitatively understood using shell model considerations. This mass region provides an excellent testing ground for the competition between allowed and first-forbidden β-decay calculations, important for the detailed understanding of the nucleosynthesis of heavy elements. ; The research leading to these results received funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 654002. Support from the European Union Seventh Framework through ENSAR Contract No. 262010, as well as the Science and Technology Facilities Council (U.K.) through Grants No. ST/P005314/1, No. ST/L005743/1, No. ST/J000051/1, No. ST/L005670/1, and No. ST/P004598/1, the German BMBF under Contract No. 05P18PKCIA and "Verbundprojekt 05P2018" as well as Spanish MINECO Grants No. FPA2015-65035- P and No. FPA2017-87568-P, FWO Vlaanderen (Belgium), GOA/2015/010 (BOF KU Leuven), the Excellence of Science Programme (EOS-FWO), the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12), the Polish National Science Centre under Contracts No. UMO-2015/18/M/ST2/00523 and No. UMO-2019/33/N/ST2/03023, National Science Foundation (U.S.) Grant No. PHY1811855, and the Romanian IFA project CERN-RO/ISOLDE is acknowledged. P.H.R. acknowledges support from the U.K. Department for Business, Energy and Industrial Strategy via the National Measurement Office ; Peer reviewed

New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the 15O +p +pthree-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of data from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. The resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure. ; This project is supported by NAVI, GSI-TU Darmstadt cooperation, HIC for FAIR, EMMI and BMBF. C.A.B. acknowledges support from the U.S. NSF Grant No. 1415655, and U.S. DOE grant No. DEFG02- 08ER41533. The work was also supported by the Spanish government grant FPA2012-32443 and the Swedish Research Council ; SI

18 pags., 11 figs., 4 tabs. ; The structure of the doubly magic Sn8250132 has been investigated at the ISOLDE facility at CERN, populated both by the β-decay of In132 and β - delayed neutron emission of In133. The level scheme of Sn132 is greatly expanded with the addition of 68 γ transitions and 17 levels observed for the first time in the β decay. The information on the excited structure is completed by new γ transitions and states populated in the β-n decay of In133. Improved delayed neutron emission probabilities are obtained both for In132 and In133. Level lifetimes are measured via the advanced time-delayed βγγ(t) fast-timing method. An interpretation of the level structure is given based on the experimental findings and the particle-hole configurations arising from core excitations both from the N = 82 and Z = 50 shells, leading to positive- and negative-parity particle-hole multiplets. The experimental information provides new data to challenge the theoretical description of Sn132. ; We acknowledge the support of the ISOLDE Collaboration and the ISOLDE technical teams, and by the European Union Horizon 2020 research and innovation programme under Grant Agreement No. 654002. This work was partially funded by the Spanish government via Projects No. FPA2015- 65035-P, No. FPA-64969-P, No. FPA2017-87568-P, and No. RTI2018-098868-B-I00; the Polish National Science Center under Contracts No. UMO-2015/18/E/ST2/00217, No. UMO-2015/18/M/ST2/00523, and No. UMO2019/33/N/ST2/03023; the Portuguese FCT via CERN/FIS-NUC/0004/2015 project; the German BMBF under Contract No. 05P18PKCIA; the Romanian IFA Grant CERN/ISOLDE; and by grants from the U.K. Science and Technology Facilities Council, the Research Foundation Flanders (FWO, Belgium), the Excellence of Science program (EOS, FWO-FNRS, Belgium), and the GOA/2015/010 (BOF KU Leuven). J.B. acknowledges support from the Universidad Complutense de Madrid under the Predoctoral Grant No. CT27/16-CT28/16

13 pags., 7 figs., 3 tabs. ; A new β-decaying state in Bi214 has been identified at the ISOLDE Decay Station at the CERN-ISOLDE facility. A preferred Iπ=(8-) assignment was suggested for this state based on the β-decay feeding pattern to levels in Po214 and shell-model calculations. The half-life of the Iπ=(8-) state was deduced to be T1/2=9.39(10) min. The deexcitation of the levels populated in Po214 by the β decay of this state was investigated via γ-γ coincidences and a number of new levels and transitions was identified. Shell-model calculations for excited states in Bi214 and Po214 were performed using two different effective interactions: the H208 and the modified Kuo-Herling particle interaction. Both calculations agree on the interpretation of the new β-decaying state as an Iπ=8- isomer and allow for tentative assignment of shell-model states to several high-spin states in Po214. ; This work has been supported by the Research Foundation Flanders (FWO, Belgium), by GOA/2015/010 (BOF KU Leuven), the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12), by the ENSAR2: European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 654002, by the U.K. Science and Technology Facilities Council, by the Slovak Research and Development Agency (Contract No. APVV-18-0268), by the Slovak grant agency VEGA (Contract No. 1/0651/21), by RFBR according to the research project N 19-02-00005, by the Romanian IFA Grant CERN/ISOLDE, by the Spanish Funding Agency (AEI) under the project PID2019-104390GB-I00, by the German BMBF under Grant No. 05P18PKCIA and by the Spanish Ministerio de Ciencia e Innovación grant PID2019-104714GB-C21. M.S. acknowledges funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 771036 (ERC CoG MAIDEN). ; Peer reviewed