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1.
  • 2017
  • swepub:Mat__t
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2.
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3.
  • Bergmann, U. C., et al. (författare)
  • Beta-decay properties of the neutron-rich Kr94-99 and Xe142-147 isotopes
  • 2003
  • Ingår i: Nuclear Physics A. - 0375-9474. ; 714:1-2, s. 21-43
  • Tidskriftsartikel (refereegranskat)abstract
    • Beta-decay half-lives and delayed-neutron emission probabilities of the neutron-rich noble-gas isotopes Kr94-99 and Xe142-147 have been measured at the PSB-ISOLDE facility at CERN. The results are compared to QRPA shell-model predictions and are used in dynamic calculations of r-process abundances of Kr and Xe isotopes. (C) 2002 Elsevier Science B.V. All rights reserved.
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4.
  • Bergmann, U. C., et al. (författare)
  • Production yields of noble-gas isotopes from ISOLDE UCx/graphite targets
  • 2003
  • Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 204, s. 220-224
  • Tidskriftsartikel (refereegranskat)abstract
    • Yields of He, Ne, Ar, Kr and Xe isotopic chains were measured from UCx/graphite and ThCx/graphite targets at the PSB-ISOLDE facility at CERN using isobaric selectivity achieved by the combination of a plasma-discharge ion source with a water-cooled transfer line. The delay times measured for a UCx/graphite target allow for an extrapolation to the expected yields of very neutron-rich noble gas isotopes, in particular for the "NuPECC reference elements" Ar and Kr, at the next-generation radioactive ion-beam facility EURISOL. (C)2003 Elsevier Science B.V. All rights reserved.
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5.
  • Fynbo, H. O. U., et al. (författare)
  • News on C-12 from beta-decay studies
  • 2004
  • Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 738, s. 59-65
  • Konferensbidrag (refereegranskat)abstract
    • We discuss the importance of the spectroscopic properties of the resonances of C-12 just above the 3alpha-threshold, and review the existing experimental information of this region with emphasis on 0(+) and 2(+) states. A new experimental approach for studying the beta-decays of B-12 and N-12 is presented based on techniques developed in the context of Radioactive beam (rare isotope) physics. Finally preliminary results from an ongoing analysis of two recent experiments are given.
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6.
  • Fynbo, H. O. U., et al. (författare)
  • Revised rates for the stellar triple-alpha process from measurement of C-12 nuclear resonances
  • 2005
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687 .- 1476-4679. ; 433:7022, s. 136-139
  • Tidskriftsartikel (refereegranskat)abstract
    • In the centres of stars where the temperature is high enough, three alpha-particles (helium nuclei) are able to combine to form C-12 because of a resonant reaction leading to a nuclear excited state(1). (Stars with masses greater than similar to0.5 times that of the Sun will at some point in their lives have a central temperature high enough for this reaction to proceed.) Although the reaction rate is of critical significance for determining elemental abundances in the Universe(1), and for determining the size of the iron core of a star just before it goes supernova(2), it has hitherto been insufficiently determined(2). Here we report a measurement of the inverse process, where a C-12 nucleus decays to three alpha-particles. We find a dominant resonance at an energy of similar to11 MeV, but do not confirm the presence of a resonance at 9.1 MeV (ref. 3). We show that interference between two resonances has important effects on our measured spectrum. Using these data, we calculate the triple-a rate for temperatures from 10(7) K to 10(10) K and find significant deviations from the standard rates(3). Our rate below similar to5 x 10(7) K is higher than the previous standard, implying that the critical amounts of carbon that catalysed hydrogen burning in the first stars are produced twice as fast as previously believed(4). At temperatures above 10(9) K, our rate is much less, which modifies predicted nucleosynthesis in supernovae(5,6).
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7.
  • Georg, U., et al. (författare)
  • Isotope production comparison at ISOLDE with 1 and 1.4 GeV protons
  • 2002
  • Ingår i: Nuclear Physics A. - 0375-9474. ; 701, s. 137C-143C
  • Konferensbidrag (refereegranskat)abstract
    • The difference in isotope production between 1 and 1.4 GeV proton projectiles was investigated at ISOLDE/CERN during the year 1999. As target materials uranium carbide, thorium carbide, lead and lanthanum oxide were used and the ratio of the measured production yields for the two different projectile energies were determined for isotopes of the elements francium, mercury, thallium, xenon, cesium, krypton, rubidium and neon. A comparison of these experimental results with the predictions from a two-step reaction model Monte-Carlo code shows good agreement. (C) 2002 Elsevier Science B.V. All rights reserved.
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8.
  • Niedermaier, O., et al. (författare)
  • "Safe" Coulomb excitation of Mg-30
  • 2005
  • Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 94:17, s. 172501 (artno)-
  • Tidskriftsartikel (refereegranskat)abstract
    • We report on the first radioactive beam experiment performed at the recently commissioned REX-ISOLDE facility at CERN in conjunction with the highly efficient γ spectrometer MINIBALL. Using Mg-30 ions accelerated to an energy of 2.25 MeV/u together with a thin Ni-nat target, Coulomb excitation of the first excited 2(+) states of the projectile and target nuclei well below the Coulomb barrier was observed. From the measured relative deexcitation γ-ray yields the B(E2;0(gs)(+)→ 2(1)(+)) value of Mg-30 was determined to be 241(31)e(2) fm(4). Our result is lower than values obtained at projectile fragmentation facilities using the intermediate-energy Coulomb excitation method, and confirms the theoretical conjecture that the neutron-rich magnesium isotope Mg-30 resides outside the "island of inversion."
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9.
  • Niedermaier, O., et al. (författare)
  • The neutron-rich Mg isotopes: first results from MINIBALL at REX-ISOLDE
  • 2005
  • Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 752, s. 273-273
  • Tidskriftsartikel (refereegranskat)abstract
    • We report on the first radioactive beam experiment performed at the recently commissioned REX-ISOLDE facility at CERN in conjunction with the highly efficient γ spectrometer MINIBALL. Using Mg-30 ions accelerated to an energy of 2.25 MeV/u together with a thin Ni-nat target, Coulomb excitation of the first excited 2(+) states of the projectile and target nuclei well below the Coulomb barrier was observed. From the measured relative deexcitation γ-ray yields the B(E2;0(gs)(+)→ 2(1)(+)) value of Mg-30 was determined to be 241(31)e(2) fm(4). Our result is lower than values obtained at projectile fragmentation facilities using the intermediate-energy Coulomb excitation method, and confirms the theoretical conjecture that the neutron-rich magnesium isotope Mg-30 resides outside the "island of inversion."
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10.
  • Scheit, H., et al. (författare)
  • Coulomb excitation of neutron-rich beams at REX-ISOLDE
  • 2005
  • Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-601X .- 1434-6001. ; 25:Suppl. 1, s. 397-402
  • Konferensbidrag (refereegranskat)abstract
    • After the successful commissioning of the radioactive beam experiment at ISOLDE (REX-ISOLDE) - an accelerator for exotic nuclei produced by ISOLDE - in 2002 and the promotion to a CERN user facility in 2003, first physics experiments using these beams were performed. Initial experiments focused on the region of deformation in the vicinity of the neutron-rich Na and Mg isotopes. Preliminary results on the neutron-rich Na and Mg isotopes show the high potential and physics opportunities offered by the exotic isotope accelerator REX in conjunction with the modern Germanium gamma spectrometer MINIBALL.
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11.
  • Ackloo, S, et al. (författare)
  • Target 2035 - an update on private sector contributions
  • 2023
  • Ingår i: RSC medicinal chemistry. - : Royal Society of Chemistry (RSC). - 2632-8682. ; 14:6, s. 1002-1011
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Target 2035, an international federation of biomedical scientists from the public and private sectors, is leveraging ‘open’ principles to develop a pharmacological tool for every human protein.
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12.
  • Campbell, PJ, et al. (författare)
  • Pan-cancer analysis of whole genomes
  • 2020
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 578:7793, s. 82-
  • Tidskriftsartikel (refereegranskat)abstract
    • Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale1–3. Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4–5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter4; identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation5,6; analyses timings and patterns of tumour evolution7; describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity8,9; and evaluates a range of more-specialized features of cancer genomes8,10–18.
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13.
  • Diget, C. A., et al. (författare)
  • Properties of the C-12 10 MeV state determined through beta-decay
  • 2005
  • Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 760:1-2, s. 3-18
  • Tidskriftsartikel (refereegranskat)abstract
    • The beta-delayed triple-alpha particle decay of B-12 has been measured with a setup that favours coincidence detection. A broad state in C-12, previously reported around 10 MeV, has been seen and its properties determined through R-matrix analysis of the excitation spectrum. The spin and parity are 0(+). Interference between this state and the Hoyle state at 7.654 MeV has a marked influence on the spectrum. The coupling between the two states makes it difficult to determine the resonance energy. (c) 2005 Elsevier B.V. All rights reserved.
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14.
  • Olaizola, B., et al. (författare)
  • High-sensitivity study of levels in Al-30 following beta decay of Mg-30
  • 2016
  • Ingår i: PHYSICAL REVIEW C. - 2469-9985 .- 2469-9993. ; 94:5
  • Tidskriftsartikel (refereegranskat)abstract
    • gamma-ray and fast-timing spectroscopy were used to study levels in Al-30 populated following the beta(-) decay of Mg-30. Five new transitions and three new levels were located in Al-30. A search was made to identify the third 1(+) state expected at an excitation energy of similar to 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) beta gamma gamma (t) method we have measured the lifetime of the 243.8-keV state to be T-1/2 = 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.
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15.
  • Shergur, J., et al. (författare)
  • beta-decay studies of Sn135-137 using selective resonance laser ionization techniques
  • 2002
  • Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 65:3
  • Tidskriftsartikel (refereegranskat)abstract
    • The decays of the very neutron rich Sn isotopes Sn135-137 were studied at CERN/ISOLDE using isotopic and isobaric selectivity achieved by the use of a resonance ionization laser ion source and mass spectroscopy, respectively. Neutron decay rates, gamma-ray singles, and gamma-gamma coincidence data were collected as a function of time. The half-life (T-1/2) and delayed neutron emission probability (P-n) values of 135 Sn were measured to be 530(20) ms and 21(3)%, respectively. For Sn-136, a T-1/2 of 250(30) ms was determined along with a P-n value of 30(5)%. For Sn-137, a T-1/2 of 190(60) ms and a P-n value of 58(15)% were deduced. Identification of low-energy transitions in Sb-135 was made possible by comparison of laser-on and laser-off gamma-ray spectra. Those data combined with gamma-gamma coincidence spectra were used to construct a level scheme for Sb-135 that includes an unexpectedly low first excited state at 282 keV. A ground state beta branch of 33.2% was measured by following the growth and decay of the Sb-135 daughter. Shell-model calculations are consistent with the observed Sb-135 level structure and can account for a lowered first excited state.
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16.
  • Weissman, L., et al. (författare)
  • beta decay of Ar-49,Ar-50
  • 2003
  • Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 67:5
  • Tidskriftsartikel (refereegranskat)abstract
    • Information on gross beta-decay properties of neutron-rich noble gas isotopes Ar-49,Ar-50 was obtained at the PSB-ISOLDE facility at CERN using isobaric selectivity achieved by the combination of a plasma ion source with a cooled transfer line and subsequent mass separation. A doubly charged beam was used in the case of Ar-49 to suppress the corresponding multicharged background from heavier noble gas fission products. The comparison of the obtained data with results of quasiparticle random-phase approximation calculations indicates that the N=28 shell is not disturbed significantly for neutron-rich Ar nuclei. The obtained results are useful for better understanding of the origin of the Ca-48/Ca-46 isotopic anomaly discovered in inclusions from the Allende meteorite.
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18.
  • Au, M., et al. (författare)
  • In-source and in-trap formation of molecular ions in the actinide mass range at CERN-ISOLDE
  • 2023
  • Ingår i: Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms. - 0168-583X. ; 541, s. 375-379
  • Tidskriftsartikel (refereegranskat)abstract
    • The use of radioactive molecules for fundamental physics research is a developing interdisciplinary field limited dominantly by their scarce availability. In this work, radioactive molecular ion beams containing actinide nuclei extracted from uranium carbide targets are produced via the Isotope Separation On-Line technique at the CERN-ISOLDE facility. Two methods of molecular beam production are studied: extraction of molecular ion beams from the ion source, and formation of molecular ions from the mass-separated ion beam in a gas-filled radio-frequency quadrupole ion trap. Ion currents of U+, UO1-3+, UC1-3+, UF1-4+, UF1,2O1,2+ are reported. Metastable tantalum and uranium fluoride molecular ions are identified. Formation of UO1-3+, U(OH)1-3+, UC1-3+, UF1,2O1,2+ from mass-separated beams of U+, UF1,2+ with residual gas is observed in the ion trap. The effect of trapping time on molecular formation is presented.
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19.
  • Balibrea-Correa, J., et al. (författare)
  • First measurement of the 94Nb(n,γ) cross section at the CERN n_TOF facility
  • 2023
  • Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 279
  • Tidskriftsartikel (refereegranskat)abstract
    • One of the crucial ingredients for the improvement of stellar models is the accurate knowledge of neutron capture cross-sections for the different isotopes involved in the s-,r- and i- processes. These measurements can shed light on existing discrepancies between observed and predicted isotopic abundances and help to constrain the physical conditions where these reactions take place along different stages of stellar evolution.In the particular case of the radioactive 94Nb, the 94Nb(n,γ) cross-section could play a role in the determination of the s-process production of 94Mo in AGB stars, which presently cannot be reproduced by state-of-the-art stellar models. There are no previous 94Nb(n,γ) experimental data for the resolved and unresolved resonance regions mainly due to the difficulties in producing highquality samples and also due to limitations in conventional detection systems commonly used in time-of-flight experiments.Motivated by this situation, a first measurement of the 94Nb(n,γ) reaction was carried out at CERN n_TOF, thereby exploiting the high luminosity of the EAR2 area in combination with a new detection system of small-volume C6D6-detectors and a high quality 94Nb-sample. The latter was based on hyper-pure 93Nb material activated at the high-flux reactor of ILL-Grenoble. An innovative ring-configuration detection system in close geometry around the capture sample allowed us to significantly enhance the signal-to-background ratio. This set-up was supplemented with two conventional C6D6-detectors and a highresolution LaCl3(Ce)-detector, which will be employed for addressing reliably systematic effects and uncertainties.At the current status of the data analysis, 18 resonance in 94Nb+n have been observed for the first time in the neutron energy range from thermal up to 10 keV.
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20.
  • Baum, R. P., et al. (författare)
  • First-in-Humans Application of Tb-161: A Feasibility Study Using Tb-161-DOTATOC
  • 2021
  • Ingår i: Journal of Nuclear Medicine. - : Society of Nuclear Medicine. - 0161-5505 .- 2159-662X. ; 62:10, s. 1391-1397
  • Tidskriftsartikel (refereegranskat)abstract
    • Tb-161 has decay properties similar to those of Lu-177 but, additionally, emits a substantial number of conversion and Auger electrons. The aim of this study was to apply Tb-161 in a clinical setting and to investigate the feasibility of visualizing the physiologic and tumor biodistributions of Tb-161-DOTATOC. Methods: Tb-161 was shipped from Paul Scherrer Institute, Villigen-PSI, Switzerland, to Zentralklinik Bad Berka, Bad Berka, Germany, where it was used for the radiolabeling of DOTATOC. In 2 separate studies, 596 and 1,300 MBq of Tb-161-DOTATOC were administered to a 35-y-old male patient with a metastatic, well-differentiated, nonfunctional malignant paraganglioma and a 70-y-old male patient with a metastatic, functional neuroendocrine neoplasm of the pancreatic tail, respectively. Whole-body planar g-scintigraphy images were acquired over a period of several days for dosimetry calculations. SPECT/CT images were reconstructed using a recently established protocol and visually analyzed. Patients were observed for adverse events after the application of Tb-161-DOTATOC. Results: The radiolabeling of DOTATOC with Tb-161 was readily achieved with a high radiochemical purity suitable for patient application. Planar images and dosimetry provided the expected time-dependent biodistribution of Tb-161-DOTATOC in the liver, kidneys, spleen, and urinary bladder. SPECT/CT images were of high quality and visualized even small metastases in bones and liver. The application of Tb-161-DOTATOC was well tolerated, and no related adverse events were reported. Conclusion: This study demonstrated the feasibility of imaging even small metastases after the injection of relatively low activities of Tb-161-DOTATOC using g-scintigraphy and SPECT/CT. On the basis of this essential first step in translating Tb-161 to clinics, further efforts will be directed toward the application of Tb-161 for therapeutic purposes.
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23.
  • Coll, M., et al. (författare)
  • Towards Oxide Electronics: a Roadmap
  • 2019
  • Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332 .- 1873-5584. ; 482, s. 1-93
  • Tidskriftsartikel (refereegranskat)abstract
    • At the end of a rush lasting over half a century, in which CMOS technology has been experiencing a constant and breathtaking increase of device speed and density, Moore’s law is approaching the insurmountable barrier given by the ultimate atomic nature of matter. A major challenge for 21st century scientists is finding novel strategies, concepts and materials for replacing silicon-based CMOS semiconductor technologies and guaranteeing a continued and steady technological progress in next decades. Among the materials classes candidate to contribute to this momentous challenge, oxide films and heterostructures are a particularly appealing hunting ground. The vastity, intended in pure chemical terms, of this class of compounds, the complexity of their correlated behaviour, and the wealth of functional properties they display, has already made these systems the subject of choice, worldwide, of a strongly networked, dynamic and interdisciplinary research community. Oxide science and technology has been the target of a wide four-year project, named Towards Oxide-Based Electronics (TO-BE), that has been recently running in Europe and has involved as participants several hundred scientists from 29 EU countries. In this review and perspective paper, published as a final deliverable of the TO-BE Action, the opportunities of oxides as future electronic materials for Information and Communication Technologies ICT and Energy are discussed. The paper is organized as a set of contributions, all selected and ordered as individual building blocks of a wider general scheme. After a brief preface by the editors and an introductory contribution, two sections follow. The first is mainly devoted to providing a perspective on the latest theoretical and experimental methods that are employed to investigate oxides and to produce oxide-based films, heterostructures and devices. In the second, all contributions are dedicated to different specific fields of applications of oxide thin films and heterostructures, in sectors as data storage and computing, optics and plasmonics, magnonics, energy conversion and harvesting, and power electronics.
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24.
  • de Walle, J. V., et al. (författare)
  • Coulomb excitation of the N=50 nucleus Zn-80
  • 2008
  • Ingår i: AIP Conference Proceedings. - 1551-7616 .- 0094-243X. ; 1012, s. 291-295 453
  • Konferensbidrag (refereegranskat)abstract
    • Neutron rich Zinc isotopes, including the N=50 nucleus Zn-80, were produced and post-accelerated at the Radioactive Ion Beam (RIB) facility REX-ISOLDE (CERN). Low-energy Coulomb excitation was induced on these isotopes after post-acceleration, yielding B(E2) strengths to the first excited 2(+) states. For the first time, an excited state in Zn-80 was observed and the 2(1)(+) state in Zn-78 was established. The measured B(E2,2(1)(+) -> 0(1)(+)) values are compared to two sets of large scale shell model calculations. Both calculations reproduce the observed B(E2) systematics for the full Zinc isotopic chain. The results for N=50 isotones indicate a good N=50 shell closure and a strong Z=28 proton core polarization. The new results serve as benchmarks to establish theoretical models, predicting the nuclear properties of the doubly magic nucleus Ni-78.
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