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R. Lica et al. -- 14 pags., 7 figs., tab. -- Open Access funded by Creative Commons Atribution Licence 3.0 ; Neutron-rich Ba isotopes are expected to exhibit octupolar correlations, reaching their maximum in isotopes around mass A = 146. The odd-A neutron-rich members of this isotopic chain show typical patterns related to non-axially symmetric shapes, which are however less marked compared to even-A ones, pointing to a major contribution from vibrations. In the present paper we present results from a recent study focused on Cs β-decay performed at the ISOLDE Decay Station equipped with fast-timing detectors. A detailed analysis of the measured decay half-lives and decay scheme of Ba is presented, giving a first insight in the structure of this neutron-rich nucleus. ; The IDS collaboration acknowledges financial support from: Istituto Nazionale di Fisica Nucleare, the Italian 'Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale (PRIN)' contract number 2001024324 01302, the European Union's seventh framework through ENSAR, contract no. 262010, the European Unions Horizon 2020 Framework research and innovation programme under grant agreement no. 654002 (ENSAR2), the FATIMA-NuPNET network via the PRI-PIMNUP-2011-1338 project, the Spanish MINECO projects reference numbers FPA2013-41467-P and FPA2015-646969-P, the German BMBF under contract 05P15PKCIA and 'Verbundprojekt 05P2015', the FWO-Vlaanderen (Belgium) and the IAP Belgian Science Policy (BriX network P7/12). VCh and ZP acknowledge support by the polish grant of Narodowe Centrum Nauki nr 2015/18/M/ST2/00523. ; Peer Reviewed

19 pags., 14 figs., 3 tabs. ; The decay of the neutron-rich and was investigated experimentally in order to provide new insights into the nuclear structure of the tin isotopes with magic proton number above the shell. The -delayed -ray spectroscopy measurement was performed at the ISOLDE facility at CERN, where indium isotopes were selectively laser-ionized and on-line mass separated. Three -decay branches of were established, two of which were observed for the first time. Population of neutron-unbound states decaying via rays was identified in the two daughter nuclei of and , at excitation energies exceeding the neutron separation energy by 1 MeV. The -delayed one- and two-neutron emission branching ratios of were determined and compared with theoretical calculations. The -delayed one-neutron decay was observed to be dominant -decay branch of even though the Gamow-Teller resonance is located substantially above the two-neutron separation energy of . Transitions following the decay of are reported for the first time, including rays tentatively attributed to . In total, six new levels were identified in on the basis of the coincidences observed in the and decays. A transition that might be a candidate for deexciting the missing neutron single-particle state in was observed in both decays and its assignment is discussed. Experimental level schemes of and are compared with shell-model predictions. Using the fast timing technique, half-lives of the , and levels in were determined. From the lifetime of the state measured for the first time, an unexpectedly large transition strength was deduced, which is not reproduced by the shell-model calculations. ; M.P.-S. acknowledges the funding support from the Polish National Science Center under Grants No. 2019/33/N/ST2/03023 and No. 2020/36/T/ST2/00547 (Doctoral scholarship ETIUDA). J.B. acknowledges support from the Universidad Complutense de Madrid under the Predoctoral Grant No. CT27/16- CT28/16. This work was partially funded by the Polish National Science Center under Grants No. 2020/39/B/ST2/02346, No. 2015/18/E/ST2/00217, and No. 2015/18/M/ST2/00523, by the Spanish government via Projects No. FPA2017-87568-P, No. RTI2018-098868-B-I00, No. PID2019-104390GB-I00, and No. PID2019-104714GB-C21, by the U.K. Science and Technology Facilities Council (STFC), the German BMBF under Contract No. 05P18PKCIA, by the Portuguese FCT under the Projects No. CERN/FIS-PAR/0005/2017, and No. CERN/FIS-TEC/0003/2019, and by the Romanian IFA Grant CERN/ISOLDE. The research leading to these results has received funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 654002. M.Str. acknowledges the funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 771036 (ERC CoG MAIDEN). J.P. acknowledges support from the Academy of Finland (Finland) with Grant No. 307685. Work at the University of York was supported under STFC Grants No. ST/L005727/1 and No. ST/P003885/1.

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

12 pags., 11 figs., 3 tabs. -- Open Access funded by Creative Commons Atribution Licence 4.0 ; The occurrence of octupolar shapes in the Ba isotopic chain was recently established experimentally up to N = 90. To further extend the systematics, the evolution of shapes in the most neutron-rich members of the Z = 56 isotopic chain accessible at present, Ba-148,Ba-150, has been studied via beta decay at the ISOLDE Decay Station. This paper reports on the first measurement of the positive-and negative-parity low-spin excited states of 150Ba and presents an extension of the beta-decay scheme of Cs-148. Employing the fast timing technique, half-lives for the 2(1)(+) level in both nuclei have been determined, resulting in T-1/2 = 1.51(1) ns for Ba-148 and T-1/2 = 3.4(2) ns for Ba-150. The systematics of low-spin states, together with the experimental determination of the B(E2 : 2(+) -> 0(+)) transition probabilities, indicate an increasing collectivity in Ba148-150, towards prolate deformed shapes. The experimental data are compared to symmetry conserving configuration mixing (SCCM) calculations, confirming an evolution of increasingly quadrupole deformed shapes with a definite octupolar character. ; The IDS Collaboration acknowledges financial support from Istituto Nazionale di Fisica Nucleare, the Italian "Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale" (PRIN), contract 2001024324 01302; the European Union seventh framework through ENSAR, contract 262010; the European Unions Horizon 2020 Framework research and innovation program under grant agreement 654002 (ENSAR2); the FATIMA-NuPNET network via the PRI-PIMNUP-2011-1338 project; the Romanian IFA grant CERN/ISOLDE and Romanian PN-II-RU-TE-2014-4-2003; the Spanish MINECO projects, reference numbers FPA2013- 41467-P, FPA2015-64969-P, FPA2015-65929, and FIS2015- 63770; Spanish grants FIS-2014-53434-P MINECO and Programa Ramon y Cajal 2012 No. 11420, MINECO grant IJCI-2014-19172, and the MINECO project FPA2014-52823- C2-1-P; the German BMBF under contract 05P15PKCIA, contract 05P15PKFNA, and "Verbundprojekt 05P2015," the FWO-Vlaanderen (Belgium); and the IAP Belgian Science Policy (BriX network P7/12). V.Ch. and Z.P. acknowledge support by the Polish grant of Narodowe Centrum Nauki, no. 2015/18/M/ST2/00523. ; Peer Reviewed

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

10 pags., 8 figs., 1 tab.-- Open Access funded by Creative Commons Atribution Licence 4.0 ; Excited states in Sn133 were investigated through the ß decay of In133 at the ISOLDE facility. The ISOLDE Resonance Ionization Laser Ion Source (RILIS) provided isomer-selective ionization for In133, allowing us to study separately, and in detail, the ß-decay branch of In133J¿=(9/2+) ground state and its J¿=(1/2-) isomer. Thanks to the large spin difference of the two ß-decaying states of In133, it is possible to investigate separately the lower and higher spin states in the daughter, Sn133, and thus to probe independently different single-particle and single-hole levels. We report here new ¿ transitions observed in the decay of In133, including those assigned to the deexcitation of the neutron-unbound states. ; We acknowledge the support of the ISOLDE Collaboration and technical teams. This work was supported in part by the Polish National Science Center under Contract No. UMO-2015/18/E/ST2/00217 and under Contract No. UMO-2015/18/M/ST2/00523, by the Spanish MINECO via FPA2015-65035-P project, by the Portuguese FCT via CERN/FIS-NUC/0004/2015 and CERN-FIS-PAR-0005-2017 projects. The research leading to these results has received funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 654002.