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1.	Akkoyun, S., et al. (författare) AGATA - Advanced GAmma Tracking Array 2012 Ingår i: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002 .- 0167-5087 .- 1872-9576. ; 668, s. 26-58 Tidskriftsartikel (refereegranskat)abstract The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation γ-ray spectrometer. AGATA is based on the technique of γ-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a γ ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of γ-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector- response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer. © 2011 Elsevier B.V. All rights reserved.
2.	Patrignani, C., et al. (författare) REVIEW OF PARTICLE PHYSICS : Particle Data Group 2016 Ingår i: Chinese Physics C. - : IOP Publishing. - 1674-1137 .- 2058-6132. ; 40:10 Tidskriftsartikel (refereegranskat)abstract The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,062 new measurements from 721 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Among the 117 reviews are many that are new or heavily revised, including new reviews on Pentaquarks and Inflation. The complete Review is published online in a journal and on the website of the Particle Data Group (http://pdg.lbl.gov). The printed PDG Book contains the Summary Tables and all review articles but no longer includes the detailed tables from the Particle Listings. A Booklet with the Summary Tables and abbreviated versions of some of the review articles is also available.
3.	Olive, K. A., et al. (författare) REVIEW OF PARTICLE PHYSICS Particle Data Group 2014 Ingår i: Chinese Physics C. - : IOP Publishing. - 1674-1137 .- 2058-6132. ; 38:9 Forskningsöversikt (refereegranskat)abstract The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 Japers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as heavy neutrinos, supersymmetric and technicolor particles, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Supersymmetry, Extra Dimensions, Particle Detectors, Probability, and Statistics. Among the 112 reviews are many that are new or heavily revised including those on: Dark Energy, Higgs Boson Physics, Electroweak Model, Neutrino Cross Section Measurements, Monte Carlo Neutrino Generators, Top Quark, Dark Matter, Dynamical Electroweak Symmetry Breaking, Accelerator Physics of Colliders, High-Energy Collider Parameters, Big Bang Nucleosynthesis, Astrophysical Constants and Cosmological Parameters.
4.	Nakamura, K., et al. (författare) Review Of Particle Physics 2010 Ingår i: Journal of Physics G: Nuclear and Particle Physics. - 0954-3899 .- 1361-6471. ; 37:7A, s. 1-1422 Forskningsöversikt (refereegranskat)abstract This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2158 new measurements from 551 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on neutrino mass, mixing, and oscillations, QCD, top quark, CKM quark-mixing matrix, V-ud & V-us, V-cb & V-ub, fragmentation functions, particle detectors for accelerator and non-accelerator physics, magnetic monopoles, cosmological parameters, and big bang cosmology. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.1b1.gov.
5.	Yao, W-M, et al. (författare) Review of Particle Physics 2006 Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 33:1, s. 1-1 Tidskriftsartikel (refereegranskat)
6.	Polettini, M., et al. (författare) Decay studies in the A∼225 Po-Fr region from the DESPEC campaign at GSI in 2021 2022 Ingår i: Il Nuovo Cimento. - : Società Italiana di Fisica. - 2037-4909. ; 45:5 Tidskriftsartikel (refereegranskat)abstract The HISPEC-DESPEC collaboration aims at investigating the structure of exotic nuclei formed in fragmentation reactions with decay spectroscopy measurements, as part of the FAIR Phase-0 campaign at GSI. This paper reports on first results of an experiment performed in spring 2021, with a focus on beta-decaystudies in the Po-Fr nuclei in the 220 < A <230 island of octupole deformation exploiting the DESPEC setup. Ion-beta correlations and fast-timing techniques are being employed, giving an insight into this difficult-to-reach region.
7.	Boso, A., et al. (författare) Isospin dependence of electromagnetic transition strengths among an isobaric triplet 2019 Ingår i: Physics Letters B. - : ELSEVIER. - 0370-2693 .- 1873-2445. ; 797 Tidskriftsartikel (refereegranskat)abstract Electric quadrupole matrix elements, M-p, for the J(pi) = 2(+) -> 0(+), Delta T = 0, T = 1 transitions across the A = 46 isobaric multiplet Cr-46-V-46-Ti-46 have been measured at GSI with the FRS-LYCCA-AGATA setup. This allows direct insight into the isospin purity of the states of interest by testing the linearity of M-p with respect to T-z. Pairs of nuclei in the T = 1 triplet were studied using identical reaction mechanisms in order to control systematic errors. The M-p values were obtained with two different methodologies: (i) a relativistic Coulomb excitation experiment was performed for Cr-46 and Ti-46; (ii) a "stretched target" technique was adopted here, for the first time, for lifetime measurements in V-46 and Ti-46. A constant value of M-p across the triplet has been observed. Shell-model calculations performed within the fp shell fail to reproduce this unexpected trend, pointing towards the need of a wider valence space. This result is confirmed by the good agreement with experimental data achieved with an interaction which allows excitations from the underlying sd shell. A test of the linearity rule for all published data on complete T = 1 isospin triplets is presented. (C) 2019 The Author(s). Published by Elsevier B.V.
8.	Gottardo, A., et al. (författare) New Isomers in the Neutron-Rich Region Beyond 208Pb 2014 Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. - 9782759811755 - 9782759811762 ; 66, s. 02043-02043 Konferensbidrag (refereegranskat)abstract The region of neutron-rich nuclei beyond 208Pb has been very difficult to explore due to its high mass and exoticity. However, recent experimental improvements allowed one to perform a quite extended isomer decay spectroscopy of these nuclei.
9.	Benzoni, G., et al. (författare) First Measurement of Beta Decay Half-lives in Neutron-rich Tl and Bi Isotopes 2012 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 715:4-5, s. 293-297 Tidskriftsartikel (refereegranskat)abstract Neutron-rich isotopes around lead, beyond N = 126, have been studied exploiting the fragmentation of an uranium primary beam at the FRS-RISING setup at GSI. For the first time beta-decay half-lives of Bi-219 and Tl-211,Tl-212,Tl-213 isotopes have been derived. The half-lives have been extracted using a numerical simulation developed for experiments in high-background conditions. Comparison with state of the art models used in r-process calculations is given, showing a systematic underestimation of the experimental values, at variance from close-lying nuclei. (c) 2012 Elsevier B.V. All rights reserved.
10.	Gottardo, A., et al. (författare) Isomeric Decay Spectroscopy of the 217Bi Isotope 2014 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 90:3 Tidskriftsartikel (refereegranskat)abstract The structure of the neutron-rich bismuth isotope 217Bi has been studied for the first time. The fragmentation of a primary 238U beam at the FRS-RISING setup at GSI was exploited to perform γ-decay spectroscopy, since μs isomeric states were expected in this nucleus. Gamma rays following the decay of a t1/2=3 μs isomer were observed, allowing one to establish the low-lying structure of 217Bi. The level energies and the reduced electric quadrupole transition probability B(E2) from the isomeric state are compared to large-scale shell-model calculations.
11.	Gottardo, A., et al. (författare) New Isomers in the Full Seniority Scheme of Neutron-rich Lead Isotopes: The Role of Effective Three-body Forces 2012 Ingår i: Physical Review Letters. - 1079-7114. ; 109:16 Tidskriftsartikel (refereegranskat)abstract The neutron-rich lead isotopes, up to Pb-216, have been studied for the first time, exploiting the fragmentation of a primary uranium beam at the FRS-RISING setup at GSI. The observed isomeric states exhibit electromagnetic transition strengths which deviate from state-of-the-art shell-model calculations. It is shown that their complete description demands the introduction of effective three-body interactions and two-body transition operators in the conventional neutron valence space beyond Pb-208.
12.	Gottardo, A., et al. (författare) New spectroscopic information on 211,213Tl : A changing structure beyond the N=126 shell closure 2019 Ingår i: Physical Review C. - 2469-9985. ; 99:5 Tidskriftsartikel (refereegranskat)abstract The neutron-rich isotopes 211,213Tl, beyond the N=126 shell closure, have been studied for the first time in isomer γ-ray decay, exploiting the fragmentation of a primary uranium beam at the Fragment Separator-Rare Isotopes Investigation at GSI setup. The observed isomeric states in 211,213Tl show a deviation from the seniority-like scheme of 209Tl. The possible interpretation of the data is discussed on the basis of energy-level systematics and shell-model calculations.
13.	Gottardo, A., et al. (författare) New μs Isomers in the Neutron-rich 210Hg Nucleus 2013 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 725:4-5, s. 292-296 Tidskriftsartikel (refereegranskat)abstract Neutron-rich nuclei in the lead region, beyond N = 126, have been studied at the FRS-RISING setup at GSI, exploiting the fragmentation of a primary uranium beam. Two isomeric states have been identified in Hg-210: the 8(+) isomer expected from the seniority scheme in the vg(9/2) shell and a second one at low spin and low excitation energy. The decay strength of the 8(+) isomer confirms the need of effective three-body forces in the case of neutron-rich lead isotopes. The other unexpected low-lying isomer has been tentatively assigned as a 3(-) state, although this is in contrast with theoretical expectations. (C) 2013 Elsevier B.V. All rights reserved.
14.	Doornenbal, P., et al. (författare) RISING: Gamma‐ray Spectroscopy with Radioactive Beams at GSI 2007 Ingår i: AIP Conference Proceedings. - : AIP. - 0094-243X. - 9780735413283 ; 891, s. 99-107 Konferensbidrag (refereegranskat)abstract The Rare Isotope Spectroscopic INvestigation at GSI (RISING) project is a major pan‐European collaboration. Its physics aims are the studies of exotic nuclear matter with abnormal proton‐to‐neutron ratios compared with naturally occurring isotopes. RISING combines the FRagment Separator (FRS) which allows relativistic energies and projectile fragmentation reactions with EUROBALL Ge Cluster detectors for γ spectroscopic research. The RISING setup can be used in two different configurations. Either the nuclei of interest are investigated after being stopped or the heavy ions hit a secondary target at relativistic energies and the thereby occurring excitations are studied. For the latter case, MINIBALL Ge detectors and the HECTOR array are used in addition. Example achievements of the Fast Beam setup are presented and compared to various shell model calculations, while for the Stopped Beam setup initial results are shown.
15.	Morales, A.I., et al. (författare) β-decay Studies of Neutron-rich Tl, Pb, and Bi Isotopes 2014 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 89:1 Tidskriftsartikel (refereegranskat)abstract The fragmentation of relativistic uranium projectiles has been exploited at the Gesellschaft für Schwerionenforschung laboratory to investigate the β decay of neutron-rich nuclei just beyond 208Pb. This paper reports on β-delayed γ decays of 211–213Tl, 215Pb, and 215–219Bi de-exciting states in the daughters 211–213Pb, 215Bi, and 215–219Po. The resulting partial level schemes, proposed with the help of systematics and shell-model calculations, are presented. The role of allowed Gamow-Teller and first-forbidden β transitions in this mass region is discussed.
16.	Schlegel, C, et al. (författare) K-isomers in very neutron-rich nuclei around mass 180 2000 Ingår i: Physica Scripta. Topical Issues. - 0281-1847. ; T88, s. 72-76 Tidskriftsartikel (refereegranskat)abstract gamma-spectroscopy methods have been used to search for microsecond isomers among the fragmentation products of a 1 GeV/nucleon Pb-208 beam. In particular the population of the known K-pi = 35/2(-) isomer in W-179 has been investigated and several new isomeric decays have been found for neutron rich nuclei in the A approximate to 180-200 mass region. The ground state band of the neutron rich N = 116 system of W-190 has been identified for the first time and we discuss its structure in comparison to neighboring systems.
17.	Avigo, R., et al. (författare) Low-lying electric dipole gamma-continuum for the unstable Fe-62,64 nuclei : Strength evolution with neutron number 2020 Ingår i: Physics Letters B. - : ELSEVIER. - 0370-2693 .- 1873-2445. ; 811 Tidskriftsartikel (refereegranskat)abstract The gamma-ray emission from the nuclei Fe-62,Fe-64 following Coulomb excitation at bombarding energy of 400-440 AMeV was measured with special focus on E1 transitions in the energy region 4-8 MeV. The unstable neutron-rich nuclei Fe-62,Fe-64 were produced at the FAIR-GSI laboratories and selected with the FRS spectrometer. The gamma decay was detected with AGATA. From the measured gamma-ray spectra the summed E1 strength is extracted and compared to microscopic quasi-particle phonon model calculations. The trend of the E1 strength with increasing neutron number is found to be fairly well reproduced with calculations that assume a rather complex structure of the 1(-) states (three-phonon states) inducing a strong fragmentation of the E1 nuclear response below the neutron binding energy.
18.	Gottardo, A., et al. (författare) Isomers in Neutron-rich Lead Isotopes Populated via the Fragmentation of 238U at 1 GeV A 2011 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 312 Tidskriftsartikel (refereegranskat)abstract Neutron-rich nuclei beyond N = 126 in the lead region were populated by fragmenting a 238U beam at 1 GeV A on a Be target and then separated by the Fragment Separator (FRS) at GSI. Their isomeric decays were observed, enabling study of the shell structure of neutron-rich nuclei around the Z=82 shell closure. Some preliminary results are reported in this paper.
19.	Podolyák, Zs, et al. (författare) Role of the Δ Resonance in the Population of a Four-Nucleon State in the 56Fe → 54Fe Reaction at Relativistic Energies 2016 Ingår i: Physical Review Letters. - 0031-9007. ; 117:22 Tidskriftsartikel (refereegranskat)abstract The Fe54 nucleus was populated from a 56Fe beam impinging on a Be target with an energy of E/A=500 MeV. The internal decay via γ-ray emission of the 10+ metastable state was observed. As the structure of this isomeric state has to involve at least four unpaired nucleons, it cannot be populated in a simple two-neutron removal reaction from the 56Fe ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of 54Fe, suggesting that it was populated via the decay of the Δ0 resonance into a proton. This process allows the population of four-nucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10+ metastable state in 54Fe is a consequence of the quark structure of the nucleons.
20.	Alexander, T., et al. (författare) Isomeric Ratios in 206Hg 2015 Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254. ; 46:3, s. 601-605 Tidskriftsartikel (refereegranskat)abstract Hg-206 was populated in the fragmentation of an E/A = 1 GeV Pb-208 beam at GSI. It was part of a campaign to study nuclei around Pb-208 via relativistic Coulomb excitation. The observation of the known isomeric states confirmed the identification of the fragmentation products. The isomeric decays were also used to prove that the correlations between beam identification detectors and the AGATA gamma-ray tracking array worked properly and that the tracking efficiency was independent of the time relative to the prompt flash.
21.	Bruce, A. M., et al. (författare) Beta Decay of 102Y Produced in Projectile Fission of 238U 2012 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 381 Tidskriftsartikel (refereegranskat)abstract The population of 102Zr following the β decay of 102Y produced in the projectile fission of 238U at the GSI facility in Darmstadt, Germany has been studied. 102Y is known to ß decay into 102Zr via two states, one of high spin and the other low spin. These states preferentially populate different levels in the 102Zr daughter. In this paper the intensities of transitions in 102Zr observed are compared with those from the decay of the low-spin level studied at the TRISTAN facility at Brookhaven National Laboratory and of the high-spin level studied at the JOSEF separator at the Kernforschungsanlage Jülich.
22.	Cox, D. M., et al. (författare) Spectroscopy along flerovium decay chains. II. Fine structure in odd-A 289Fl 2023 Ingår i: Physical Review C. - 2469-9985. ; 107:2 Tidskriftsartikel (refereegranskat)abstract Fifteen correlated α-decay chains starting from the odd-A superheavy nucleus 289Fl were observed following the fusion-evaporation reaction 48Ca+244Pu. The results call for at least two parallel α-decay sequences starting from at least two different states of 289Fl. This implies that close-lying levels in nuclei along these chains have quite different spin-parity assignments. Further, observed α-electron and α-photon coincidences, as well as the α-decay fine structure along the decay chains, suggest a change in the ground-state spin assignment between 285Cn and 281Ds. Our experimental results, on the excited level structure of the heaviest odd-N nuclei to date, provide a direct testing ground for theory. This is illustrated by comparison with new nuclear structure calculations based on the symmetry-conserving configuration mixing theory.
23.	Lalkovski, S., et al. (författare) Core-coupled states and split proton-neutron quasiparticle multiplets in Ag122-126 2013 Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 87:3, s. 034308- Tidskriftsartikel (refereegranskat)abstract Neutron-rich silver isotopes were populated in the fragmentation of a Xe-136 beam and the relativistic fission of U-238. The fragments were mass analyzed with the GSI Fragment Separator and subsequently implanted into a passive stopper. Isomeric transitions were detected by 105 high-purity germanium detectors. Eight isomeric states were observed in Ag122-126 nuclei. The level schemes of Ag-122,Ag-123,Ag-125 were revised and extended with isomeric transitions being observed for the first time. The excited states in the odd-mass silver isotopes are interpreted as core-coupled states. The isomeric states in the even-mass silver isotopes are discussed in the framework of the proton-neutron split multiplets. The results of shell-model calculations, performed for the most neutron-rich silver nuclei are compared to the experimental data.
24.	Neyens, G., et al. (författare) g-Factor Measurements on Relativistic Isomeric Beams Produced by Fragmentation and U-fission: The g-RISING Project at GSI 2007 Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254. ; 38:4, s. 1237-1247 Tidskriftsartikel (refereegranskat)abstract Within the RISING (Rare ISotope INvestigations @ GSI) Collaboration at GSI, g factor measurements have been performed on isomeric states in neutron-rich isotopes approaching Sn-132 and in the neutron deficient Pb-region (the g-RISING campaign). We present the experimental technique and some typical aspects related to such studies on relativistic beams selected with the FRS fragment separator. First results are presented for the (19/2(+)) 4.5 mu s isomeric state in Sn-127, which has been produced by means of fission of a relativistic U-238 beam on the one hand, and by the fragmentation of a relativistic Xe-136 beam on the other hand. Spin-alignment has been observed in both reactions. It was the first time that spin-alignment has been established in a relativistic fission reaction.
25.	Såmark-Roth, A., et al. (författare) Spectroscopy along flerovium decay chains. III. Details on experiment, analysis, 282Cn, and spontaneous fission branches 2023 Ingår i: Physical Review C. - 2469-9985. ; 107:2 Tidskriftsartikel (refereegranskat)abstract Flerovium isotopes (element Z = 114) were produced in the fusion-evaporation reactions 48Ca+242,244Pu and studied with an upgraded TASISpec decay station placed in the focal plane of the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. Twenty-nine flerovium decay chains were identified by means of correlated implantation, α decay, and spontaneous fission events. Data analysis aspects and statistical assessments, primarily based on measured rates of various events, which laid the foundation for the comprehensive spectroscopic information on the flerovium decay chains, are presented in detail. Various decay scenarios of an excited state observed in 282Cn are examined in depth with the help of GEANT4 simulations and assessed by predictions of beyond mean-field calculations including triaxial shape degrees of freedom. Previous, revised, and newly derived fission probabilities of even-even superheavy nuclei are compared with various theoretical predictions.
26.	Cox, D. M., et al. (författare) Spectroscopic Tools Applied to Flerovium Decay Chains 2020 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1643 Tidskriftsartikel (refereegranskat)abstract An upgraded TASISpec setup, with the addition of a veto DSSD and the new Compex detector-germanium array, has been employed with the gas-filled recoil separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt, to study flerovium (element 114) decay chains. The detector upgrades along with development of new analytical techniques have improved the sensitivity of the TASISpec setup for measuring α-photon coincidences. These improvements have been assessed with test reactions. The reaction 48Ca+206,207Pb was used for verification of experimental parameters such as transmission to implantation DSSD and target-segment to α-decay correlations. The reaction 48Ca+ natHf was used to produce several short-lived nuclei with multiple-α decay chains to investigate pile-up event deconvolution.
27.	Lalović, Nataša, et al. (författare) Study of isomeric states in 198,200,202,206Pb and 206Hg populated in fragmentation reactions 2018 Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 45:3 Tidskriftsartikel (refereegranskat)abstract Isomeric states in isotopes in the vicinity of doubly-magic 208Pb were populated following reactions of a relativistic 208Pb primary beam impinging on a 9Be fragmentation target. Secondary beams of 198,200,202,206Pb and 206Hg were isotopically separated and implanted in a passive stopper positioned in the focal plane of the GSI Fragment Separator. Delayed γ rays were detected with the Advanced Gamma Tracking Array (AGATA). Decay schemes were re-evaluated and interpreted with shell-model calculations. The momentum-dependent population of isomeric states in the two-nucleon hole nuclei 206Pb/206Hg was found to differ from the population of multi neutron-hole isomeric states in 198,200,202Pb.
28.	Lozeva, R. L., et al. (författare) New sub-us Isomers in 125Sn, 127Sn, 129Sn and Isomer Systematics of 124-130Sn 2008 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 77:6 Tidskriftsartikel (refereegranskat)abstract New sub-mu s isomers have been observed in the neutron-rich Sn isotopes. Sn-125,Sn-127,Sn-129 nuclei have been produced in a relativistic fission reaction of U-238 on a Be-9 target at 750 A.MeV and by the fragmentation of Xe-136 at 600 A.MeV populating high-spin yrast states. In addition to the already known mu s isomers, three new ones with sub-mu s half-lives have been observed. These yrast isomers are the high-spin members of the nu(d(3/2)(-1)h(11/2)(-2)) and nu h(11/2)(-n), seniority v = 3 multiplets leading to isomeric (23/2(+)) and (27/2(-)) states, respectively. Added to the already known 19/2(+)mu s isomers in this region the current work completes the systematic information of neutron-hole excitations toward the filling of the last h(11/2) orbital at N = 82. The results are discussed in the framework of state-of-the-art shell-model calculations using realistic interactions.
29.	Maierbeck, P., et al. (författare) Structure of 55Ti from relativistic one-neutron knockout 2009 Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 675:1, s. 22-27 Tidskriftsartikel (refereegranskat)abstract Results are presented from a one-neutron knockout reaction at relativistic energies on 56Ti using the GSI FRS as a two-stage magnetic spectrometer and the Miniball array for gamma-ray detection. Inclusive and exclusive longitudinal momentum distributions and cross-sections were measured enabling the determination of the orbital angular momentum of the populated states. First-time observation of the 955(6) keV -hole state in 55Ti is reported. The measured data for the first time proves that the ground state of 55Ti is a 1/2- state, in agreement with shell-model calculations using the GXPF1A interaction that predict a sizable N=34 gap in 54Ca.
30.	Pietri, S., et al. (författare) First Results from the Stopped Beam Isomer RISING Campaign at GSI 2007 Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254. ; 38:4, s. 1255-1264 Tidskriftsartikel (refereegranskat)abstract The first results from a series of experiments focused on the study of the internal structure of nuclei at the extremes of N:Z ratio using isomer spectroscopy are reported. These experiments represent the first of the Stopped Beam section of the Rare Isotopes Investigations at GSI (RISING) project. Exotic nuclei were synthesized using relativistic projectile fragmentation of similar to 500 -> 1000 MeV/u beams of Ag-107, Pb-208, Xe-136 and Ni-58, or fission of 750 MeV/u U-238 provided by the SIS synchrotron at GSI. A detailed description of the RISING stopped beam set up is given, together with a report of the performance of the associated gamma-ray spectrometer array. Selected results of the first experimental campaign are presented together with a discussion on the use of isomeric spectroscopy to study GeV range nuclear fragmentation. Details on future research plans of this collaboration are also outlined.
31.	Schwertel, S., et al. (författare) One-neutron knockout from Sc51-55 2012 Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-601X .- 1434-6001. ; 48:Dec., s. 191-10 Tidskriftsartikel (refereegranskat)abstract Results are presented from a one-neutron knockout experiment at relativistic energies of approximate to 420 A MeV on Sc51-55 using the GSI Fragment Separator as a two-stage magnetic spectrometer and the Miniball array for gamma-ray detection. Inclusive longitudinal momentum distributions and cross-sections were measured enabling the determination of the contributions corresponding to knockout from the nu p(1/2), nu p(3/2), (L = 1) and nu f(7/2), nu f(5/2) (L = 3) neutron orbitals. The observed L = 1 and L = 3 contributions are compared with theoretical cross-sections using eikonal knockout theory and spectroscopic factors from shell model calculations using the GXPF1A interaction. The measured inclusive knockout cross-sections generally follow the trends expected theoretically and given by the spectroscopic strength predicted from the shell model calculations. However, the deduced L = 1 cross-sections are generally 30-40% higher while the L = 3 contributions are about a factor of two smaller than predicted. This points to a promotion of neutrons from the nu f(7/2) to the nu p(3/2) orbital indicating a weakening of the N = 28 shell gap in these nuclei. While this is not predicted for the phenomenological GXPF1A interaction such a weakening is predicted by recent calculations using realistic low-momentum interactions V-lowk obtained by evolving a chiral N3LO nucleon-nucleon potential.
32.	Steer, S. J., et al. (författare) Isomeric States Observed in Heavy Neutron-rich Nuclei Populated in the Fragmentation of a 208Pb Beam 2011 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 84:4 Tidskriftsartikel (refereegranskat)abstract Heavy neutron-rich nuclei were populated via the fragmentation of a E/A = 1 GeV Pb-208(82) beam. Secondary fragments were separated and identified and subsequently implanted in a passive stopper. By the detection of delayed gamma rays, isomeric decays associated with these nuclei have been identified. A total of 49 isomers were detected, with the majority of them observed for the first time. The newly discovered isomers are in Hg-204,205(80), Au-201,202,204,205(79), Pt-197,203,204(78), Ir-195,199-203(77), Os-193,197-199(76), Re-196(75), W-190,191(74), and Ta-189(73). Possible level schemes are constructed and the structure of the nuclei discussed. To aid the interpretation, shell-model as well as BCS calculations were performed.
33.	Tsai, MY, et al. (författare) Spatial variation of PM elemental composition between and within 20 European study areas--Results of the ESCAPE project 2015 Ingår i: Environment international. - : Elsevier BV. - 1873-6750 .- 0160-4120. ; 84, s. 181-192 Tidskriftsartikel (refereegranskat)
34.	Valiente-Dobón, J.J., et al. (författare) Manifestation of the Berry phase in the atomic nucleus 213Pb 2021 Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 816 Tidskriftsartikel (refereegranskat)abstract The neutron-rich 213Pb isotope was produced in the fragmentation of a primary 1 GeV A 238U beam, separated in FRS in mass and atomic number, and then implanted for isomer decay γ-ray spectroscopy with the RISING setup at GSI. A newly observed isomer and its measured decay properties indicate that states in 213Pb are characterized by the seniority quantum number that counts the nucleons not in pairs coupled to angular momentum J=0. The conservation of seniority is a consequence of a geometric phase associated with particle-hole conjugation, which becomes observable in semi-magic nuclei where nucleons half-fill the valence shell. The γ-ray spectroscopic observables in 213Pb are thus found to be driven by two mechanisms, particle-hole conjugation and seniority conservation, which are intertwined through a Berry phase.
35.	Yaneva, A., et al. (författare) FAST-TIMING MEASUREMENT IN 96Pd: IMPROVED ACCURACY FOR THE LIFETIME OF THE 4+1 STATE 2023 Ingår i: Acta Physica Polonica B, Proceedings Supplement. - : Jagiellonian University. - 1899-2358 .- 2082-7865. ; , s. 1-1 Konferensbidrag (refereegranskat)abstract Direct lifetime measurements via γ–γ coincidences using the FATIMA fast-timing LaBr3(Ce) array were performed for the excited states below previously reported isomers. In the N = 50 semi-magic 96Pd nucleus, lifetimes below the Iπ = 8+ seniority isomer were addressed as a benchmark for further analysis. The results for the Iπ = 2+ and 4+ states confirm the published values. Increased accuracy for the lifetime value was achieved for the 4+ state.
36.	Zago, L., et al. (författare) High-spin states in 212Po above the α-decaying (18+) isomer 2022 Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 834 Tidskriftsartikel (refereegranskat)abstract The nucleus 212Po has been produced through the fragmentation of a 238U primary beam at 1 GeV/nucleon at GSI, separated with the FRagment Separator, FRS, and studied via isomer γ-decay spectroscopy with the RISING setup. Two delayed previously unknown γ rays have been observed. One has been attributed to the E3 decay of a 21− isomeric state feeding the α-emitting 45-s (18+) high-spin isomer. The other γ-ray line has been assigned to the decay of a higher-lying 23+ metastable state. These are the first observations of high-spin states above the 212Po (18+) isomer, by virtue of the selectivity obtained via ion-by-ion identification of 238U fragmentation products. Comparison with shell-model calculations points to shortfalls in the nuclear interactions involving high-j proton and neutron orbitals, to which the region around Z∼100 is sensitive.
37.	Atanasova, L., et al. (författare) g-factor Measurements at RISING: The Cases of 127Sn and 128Sn 2010 Ingår i: Europhysics Letters. - : IOP Publishing. - 0295-5075. ; 91:4 Tidskriftsartikel (refereegranskat)abstract We report on g-factor measurements of the 19/2(+) T-1/2 = 4.5(3) mu s isomer in Sn-127 and the 10(+) T-1/2 = 2.69(23) mu s isomer in Sn-128. These isomers were produced and spin-aligned in relativistic heavy-ion fragmentation at GSI and were selected and separated by the GSI fragment separator ( FRS). The gamma-rays of the isomeric decay were detected by the RISING gamma-ray spectrometer. The method of time-differential perturbed angular distributions was utilized. The measured g-factors, g(19/2(+); Sn-127) =-0.17(2) and g(10(+); Sn-128)=-0.20(4), are compared with shell model calculations. The measured g-factors confirm the predominantly nu h(11/2)(-2) and nu(s(1/2)(-1) h(11/2)(-2)) character of the 10(+) and 19/2(-) isomers in Sn-128 and Sn-127, respectively. The results demonstrate the feasibility of the method for similar measurements in exotic neutron-rich nuclei. Copyright (C) EPLA, 2010
38.	Caamano, M, et al. (författare) Isomers in neutron-rich A approximate to 190 nuclides from Pb-208 fragmentation 2005 Ingår i: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 23:2, s. 201-215 Tidskriftsartikel (refereegranskat)abstract Relativistic projectile fragmentation of Pb-208 has been used to produce isomers in neutron-rich, A approximate to 190 nuclides. A forward-focusing spectrometer provided ion-by-ion mass and charge identification. The detection of gamma-rays emitted by stopped ions has led to the assignment of isomers in Ta-188, W-190, Re-192, Re-193, Os-195, Ir-197, Ir-198, Pt-200, Pt-201, Pt-202 and Au-203, with half-lives ranging from approximately 10 ns to 1 ms. Tentative isomer information has been found also for Er-174, Er-175, Hf-185, Re-191, Re-194 and Ir-199. In most cases, time-correlated, singles gamma-ray events provided the first spectroscopic data on excited states for each nuclide. In Pt-200 and Pt-201. the assignments are supported by gamma-gamma coincidences. Isomeric ratios provide additional information, such as half-life and transition energy constraints in particular cases. The level structures of the platinum isotopes are discussed, and comparisons are made with isomer systematics.
39.	Denis Bacelar, A.M., et al. (författare) The population of metastable states as a probe of relativistic-energy fragmentation reactions 2013 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 723:4–5, s. 302-306 Tidskriftsartikel (refereegranskat)abstract Isomeric ratios have been measured for high-spin states in Po-198,200,206,208(84), At-208,209,210,211(85), Rn-210,211,212,213,214(86), Fr-208,211,212,213,214(87), Ra-210,211,212,214,215(88), and Ac-215(89) following the projectile fragmentation of a 1 AGeV U-238 beam by a Be-9 target at GSI Helmholtzzentrum fur Schwerionenforschung. The fragments were separated in the fragment separator (FRS) and identified by means of energy loss and time-of-flight techniques. They were brought to rest at the centre of the RISING gamma-ray detector array and intensities of gamma rays emitted in the decay of isomeric states with half-lives between 100 ns and 40 mu s and spin values up to 55/2 (h) over bar were used to obtain the corresponding isomeric ratios. The data are compared to theoretical isomeric ratios calculated in the framework of the abrasion-ablation model. Large experimental enhancements are obtained for high-spin isomers in comparison to expected values. (C) 2013 Elsevier B.V. All rights reserved.
40.	Di Nitto, A., et al. (författare) Identification of Reaction Products in 50Ti+249Cf Reactions at TASCA 2017 Ingår i: GSI Scientific Report 2016. - 0174-0814. ; 2017-1, s. 203-203 Bokkapitel (refereegranskat)
41.	Di Nitto, A., et al. (författare) Study of Non-fusion Products in the 50Ti+249Cf Reaction 2018 Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 784, s. 199-205 Tidskriftsartikel (refereegranskat)abstract The isotopic distribution of nuclei produced in the 50Ti + 249Cf reaction has been studied at the gas-filled recoil separator TASCA at GSI Darmstadt, which separates ions according to differences in magnetic rigidity. The bombardment was performed at an energy around the Bass barrier and with the TASCA magnetic fields set for collecting fusion-evaporation reaction products. Fifty-three isotopes located “north-east” of 208Pb were identified as recoiling products formed in non-fusion channels of the reaction. These recoils were implanted with energies in two distinct ranges; besides one with higher energy, a significant low-energy contribution was identified. The latter observation was not expected to occur according to kinematics of the known types of reactions, namely quasi-elastic, multi-nucleon transfer, deep-inelastic collisions or quasifission. The present observations are discussed within the framework of two-body kinematics passing through the formation of a composite system.
42.	Khuyagbaatar, J., et al. (författare) New Short-Lived Isotope 221U and the Mass Surface Near N=126 2015 Ingår i: Physical Review Letters. - 1079-7114. ; 115:24 Tidskriftsartikel (refereegranskat)abstract Two short-lived isotopes 221U and 222U were produced as evaporation residues in the fusion reaction 50Ti+176Yb at the gas-filled recoil separator TASCA. An α decay with an energy of Eα=9.31(5) MeV and half-life T1/2=4.7(7) μs was attributed to 222U. The new isotope 221U was identified in α-decay chains starting with Eα=9.71(5) MeV and T1/2=0.66(14) μs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.
43.	Maierbeck, P., et al. (författare) Probing the single particle structure around Ca-54 with one-neutron knock-out 2008 Ingår i: AIP Conference Proceedings. - 1551-7616 .- 0094-243X. ; 1012, s. 89-93 Konferensbidrag (refereegranskat)abstract The nuclei Ca-47 and Ti-55 were populated in one-neutron knock-out reactions at relativistic energies. Momentum distributions of the residual nuclei as well as gamma-ray spectra were measured at the GSI fragment separator (FRS). Preliminary results of the ongoing analysis including cross sections and spin/parity assignments are presented.
44.	Moschner, K., et al. (författare) Relativistic Coulomb excitation of 88Kr 2016 Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 94:5 Tidskriftsartikel (refereegranskat)abstract To investigate the systematics of mixed-symmetry states in N=52 isotones, a relativistic Coulomb excitation experiment was performed during the PreSPEC campaign at the GSI Helmholtzzentrum für Schwerionenforschung to determine E2 transition strengths to 2+ states of the radioactive nucleus 88Kr. Absolute transition rates could be measured towards the first and third 2+ states. For the latter a mixed-symmetry character is suggested on the basis of the indication for a strong M1 transition to the fully symmetric 2+1 state, extending the knowledge of the N=52 isotones below Z=40. A comparison with the proton-neutron interacting boson model and shell-model predictions is made and supports the assignment.
45.	Podolyák, Zs, et al. (författare) Neutron-deficient N≈126 Nuclei Produced in 238U Fragmentation : Population of High-spin States 2006 Ingår i: Frontiers in Nuclear Structure, Astrophysics, and Reactions - FINUSTAR. - : AIP. - 0735403236 - 9780735403239 ; 831, s. 114-118 Konferensbidrag (refereegranskat)abstract The population of metastable states produced in relativistic-energy fragmentation of a 238U beam has been measured. For states with high angular momentum, I=17 and I=21.5, a higher population than expected has been observed, with the discrepancy increasing with angular momentum. By considering two sources for the angular momentum, related to single-particle and collective motions, a much improved description of the experimental results can be obtained. In addition, new results on the structure of 208Fr, 211Ra and 216Ac are reported.
46.	Podolyak, Zs., et al. (författare) Structure of Neutron-rich Nuclei Around the N=126 Closed Shell; the Yrast Structure of 205Au up to Spin-parity I = (19/2+) 2009 Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 42:3, s. 489-493 Konferensbidrag (refereegranskat)abstract Heavy neutron-rich nuclei have been populated through the relativistic fragmentation of a Pb-208(82) beam at E/A = 1 GeV on a 2.5 g/cm(2) thick Be target. The synthesised nuclei were selected and identified in-flight using the fragment separator at GSI. Approximately 300 ns after production, the selected nuclei were implanted in an similar to 8 mm thick perspex stopper, positioned at the centre of the RISING gamma-ray detector spectrometer array. A previously unreported isomer with a half-life T-1/2 = 163(5) ns has been observed in the N = 126 closed-shell nucleus Au-205(79). Through gamma-ray singles and gamma-gamma coincidence analysis a level scheme was established. The comparison with a shell model calculation tentatively identifies the spin-parity of the excited states, including the isomer itself, which is found to be I-pi = (19/2(+)).
47.	Regan, P. H., et al. (författare) First Results from the Stopped RISING Campaign at GSI: The Mapping of Isomeric Decays in Highly Exotic Nuclei 2007 Ingår i: AIP Conference Proceedings. - : AIP. - 0094-243X. - 9780735413283 ; 899, s. 19-22 Konferensbidrag (refereegranskat)abstract The first results from the Stopped Beam RISING experimental campaign performed at the GSI laboratory in Darmstadt, Germany, are presented. RISING (Rare ISotope INvestigations at GSI) constitutes a major new experimental program in European nuclear structure physics research aimed at using relativistic‐energy, projectile‐fragmentation reactions to study nuclei with exotic proton‐to‐neutron ratios. This paper introduces the physics aims of the Stopped RISING collaboration and presents some technical details and initial results from experiments using the RISING array to study decays from metastable nuclear states in both proton and neutron‐rich nuclei.
48.	Rudolph, Dirk, et al. (författare) Exciting Isomers from the First Stopped-beam RISING Campaign 2007 Ingår i: The European Physical Journal. Special Topics. - : Springer Science and Business Media LLC. - 1951-6355 .- 1951-6401. ; 150, s. 173-176 Tidskriftsartikel (refereegranskat)abstract First results are reported from a major new initiative of experiments, which focus on nuclear structure studies at extreme isospin values by means of isomer spectroscopy. The experiments represent the first part of the so-called stopped-beam campaign within the Rare ISotope INvestigations at GSI (RISING) project. Time-correlated gamma decays from individually identified nuclear species have been measured, allowing the clean identification of isomeric decays in a wide range of exotic nuclei both at the proton drip-line and in heavy, neutron-rich systems. An overview of the experimental technique will be given, together with the performance of the new germanium detector array and future research plans for the collaboration.
49.	Steer, S. J., et al. (författare) Isomeric Decay Studies In Neutron-Rich N Approximate To 126 Nuclei 2009 Ingår i: International Journal Of Modern Physics E-Nuclear Physics. - 0218-3013. ; 18:4, s. 1002-1007 Konferensbidrag (refereegranskat)abstract Heavy neutron-rich nuclei were populated via relativistic energy fragmentation of a E/A= 1 GeV Pb-208 beam. The nuclei of interest were selected and identified by a fragment separator and then implanted in a passive plastic stopper. Delayed. rays following internal isomeric decays were detected by the RISING array. Experimental information was obtained on a number of nuclei with Z=73-80 (Ta-Hg), providing new information both on the prolate-oblate transitional region as well as on the N=126 closed shell nuclei.
50.	Steer, S. J., et al. (författare) Single-particle Behavior at N=126: Isomeric Decays in Neutron-rich 204Pt 2008 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:6 Tidskriftsartikel (refereegranskat)abstract The four proton-hole nucleus Pt-204 was populated in the fragmentation of an E/A = 1 GeV Pb-208 beam. The yrast structure of Pt-204 has been observed up to angular momentum I = 10h by detecting delayed gamma-ray transitions originating from metastable states. These long-lived excited states have been identified to have spin-parities of I-pi = (10(+)), (7(-)), and (5(-)) and half-lives of T-1/2 = 146(14) ns, 55(3) mu s, and 5.5(7) mu s, respectively. The structure of the magic N = 126 Pt-204 nucleus is discussed and understood in terms of the spherical shell model. The data suggest a revision of the two-body interaction for N = 126, Z < 82, which determines the evolution of nuclear structure toward the r-process waiting point nuclei.

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