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1.
  • Chumak, A. V., et al. (författare)
  • Advances in Magnetics Roadmap on Spin-Wave Computing
  • 2022
  • Ingår i: IEEE Transactions on Magnetics. - 0018-9464. ; 58:6
  • Tidskriftsartikel (refereegranskat)abstract
    • Magnonics addresses the physical properties of spin waves and utilizes them for data processing. Scalability down to atomic dimensions, operation in the GHz-to-THz frequency range, utilization of nonlinear and nonreciprocal phenomena, and compatibility with CMOS are just a few of many advantages offered by magnons. Although magnonics is still primarily positioned in the academic domain, the scientific and technological challenges of the field are being extensively investigated, and many proof-of-concept prototypes have already been realized in laboratories. This roadmap is a product of the collective work of many authors that covers versatile spin-wave computing approaches, conceptual building blocks, and underlying physical phenomena. In particular, the roadmap discusses the computation operations with Boolean digital data, unconventional approaches like neuromorphic computing, and the progress towards magnon-based quantum computing. The article is organized as a collection of sub-sections grouped into seven large thematic sections. Each sub-section is prepared by one or a group of authors and concludes with a brief description of current challenges and the outlook of further development for each research direction. Author
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2.
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3.
  • Palacz, M., et al. (författare)
  • N=50 Core Excited States Studied in the 96Pd Nucleus
  • 2012
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813 .- 1089-490X. ; 86:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The four-proton hole Pd-96 neighbor of the doubly-magic Sn-100 nucleus was studied in-beam, using a fusion-evaporation reaction of a Ni-58 beam on a Sc-45 target. States of Pd-96 were established up to an excitation energy of 9707 keV. A core-excited odd-parity isomer with T-1/2 = 37.7(1.1) ns was identified. Shell model calculations were performed in four different model spaces. Even-parity states of Pd-96 are very well reproduced in large-scale shell model (LSSM) calculations in which excitations are allowed of up to five g(9/2) protons and neutrons across the N = Z = 50 gap, to the g(7/2), d(5/2), d(3/2), and s(1/2) orbitals. The odd-parity isomer can be only qualitatively interpreted though, employing calculation in the full fpg shell model space, with just one particle-hole core excitation.
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4.
  • Palacz, M., et al. (författare)
  • Odd-Parity Sn-100 Core Excitations
  • 2013
  • Ingår i: Acta Physica Polonica B. - 0587-4254 .- 1509-5770. ; 44:3, s. 491-500
  • Tidskriftsartikel (refereegranskat)abstract
    • Odd-parity core excited states have been identified in two close neighbors of Sn-100: Pd-96 and Ag-97. This was done in an fusion-evaporation experiment, using a Ni-58 beam on a Sc-45 target. Even-parity core excited states in these nuclei are very well reproduced in large scale (LSSM) calculations in which particle-hole excitations are allowed with up to five g(9/2) protons and neutrons across the N = Z = 50 gap, to the g(7/2), d(5/2), d(3/2), and s(1/2) orbitals. The odd-parity states can only be qualitatively interpreted though, employing calculations in the full fpg shell model space, but with just one particle-hole core excitation allowed. A more complete model including odd-parity orbitals is need for the description of core excited states in the region of Sn-100. 
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5.
  • Perot, B., et al. (författare)
  • The EURITRACK project : Development of a tagged neutron inspection system for cargo containers
  • 2006
  • Ingår i: Proc SPIE Int Soc Opt Eng. - : SPIE. - 0819462691 - 9780819462695
  • Konferensbidrag (refereegranskat)abstract
    • The EURopean Illicit TRAfficing Countermeasures Kit project is part of the 6th European Union Framework Program, and aims at developing a neutron inspection system for detecting threat materials (explosives, drugs, etc.) in cargo containers. Neutron interaction in the container produces specific gamma-rays used to determine the chemical composition of the inspected material. An associated particle sealed tube neutron generator is developed to allow precise location of the interaction point by direction and time-of-flight measurements of the neutrons tagged by alpha-particles. The EURITRACK project consists in developing: a transportable deuterium-tritium neutron generator including a position sensitive alpha detector (8×8 matrix of YAP:Ce crystals coupled to a multi-anode photomultiplier), fast neutron and gamma-ray detectors, front-end electronics to perform coincidence and spectroscopic measurements, and an integrated software which manages neutron generator and detectors positioning, data acquisition and analysis. Hardware components have been developed and tested by the consortium partners. Current status of this work and provisional performances of the system assessed by Monte Carlo calculations are presented.
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6.
  • Skeppstedt, O, et al. (författare)
  • The EUROBALL neutron wall - design and performance tests of neutron detectors
  • 1999
  • Ingår i: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV. ; 421:3, s. 531-541
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • The mechanical design of the EUROBALL neutron wall and neutron detectors, and their performance measured with a Cm-246,Cm-248 fission source are described. The array consists of 15 pseudohexaconical detector units subdivided into three, 149 mm high, herme
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7.
  • Anne, R., et al. (författare)
  • Dissociation Reactions of the Be-11 One-Neutron Halo - the Interplay between Structure and Reaction-Mechanism
  • 1993
  • Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 304:1-2, s. 55-59
  • Tidskriftsartikel (refereegranskat)abstract
    • The angular distributions of the forward neutrons in the exclusive (Be-10 + n) channel have been measured. They can be accounted for quantitatively and without free parameters in terms of Coulomb and diffraction dissociation. The results show that the transverse momentum distributions result from an interplay between the tail of the wave function (the halo) and the reaction mechanism.
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8.
  • Axelsson, L., et al. (författare)
  • Study of the unbound nucleus 11N by elastic resonance scattering
  • 1996
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813 .- 2469-9985 .- 2469-9993. ; 54:4, s. 1511-1514
  • Tidskriftsartikel (refereegranskat)abstract
    • Resonances in the unbound nucleus 11N have been studied, using the resonance scattering reaction 10C+p. The data give evidence for three states above the 10C+p threshold with energies 1.30, 2.04, and 3.72 MeV. These states can be interpreted, in a potential-model analysis, as the ground state and the first two excited states with spin-parity 1 / 2+, 1 / 2-, and 5 / 2+ arising from the shell-model orbitals 1s1 / 2, 0p1 / 2, and 0d5 / 2. A narrow state superposed on a broad structure found at higher energy could be interpreted as the mirror state of the 3 / 2- in 11Be shifted down in energy. This shift would suggest a large radius of the potential.
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9.
  • Baxter, Amanda L., et al. (författare)
  • Collaborative experience between scientific software projects using Agile Scrum development
  • 2022
  • Ingår i: Software, practice & experience. - : John Wiley & Sons. - 0038-0644 .- 1097-024X. ; 52:10, s. 2077-2096
  • Tidskriftsartikel (refereegranskat)abstract
    • Developing sustainable software for the scientific community requires expertise in software engineering and domain science. This can be challenging due to the unique needs of scientific software, the insufficient resources for software engineering practices in the scientific community, and the complexity of developing for evolving scientific contexts. While open-source software can partially address these concerns, it can introduce complicating dependencies and delay development. These issues can be reduced if scientists and software developers collaborate. We present a case study wherein scientists from the SuperNova Early Warning System collaborated with software developers from the Scalable Cyberinfrastructure for Multi-Messenger Astrophysics project. The collaboration addressed the difficulties of open-source software development, but presented additional risks to each team. For the scientists, there was a concern of relying on external systems and lacking control in the development process. For the developers, there was a risk in supporting a user-group while maintaining core development. These issues were mitigated by creating a second Agile Scrum framework in parallel with the developers' ongoing Agile Scrum process. This Agile collaboration promoted communication, ensured that the scientists had an active role in development, and allowed the developers to evaluate and implement the scientists' software requirements. The collaboration provided benefits for each group: the scientists actuated their development by using an existing platform, and the developers utilized the scientists' use-case to improve their systems. This case study suggests that scientists and software developers can avoid scientific computing issues by collaborating and that Agile Scrum methods can address emergent concerns.
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10.
  • Berman, F., et al. (författare)
  • The GrADS project : Software support for high-level grid application development
  • 2001
  • Ingår i: The international journal of high performance computing applications. - : SAGE Publications. - 1094-3420 .- 1741-2846. ; 15:4, s. 327-344
  • Tidskriftsartikel (refereegranskat)abstract
    • Advances in networking technologies will soon make it possible to use the global information infrastructure in a qualitatively different way-as a computational as well as an information resource. As described in the recent book The Grid: Blueprint for a New Computing Infrastructure, this Grid will connect the nation's computers, databases, instruments, and people in a seamless web of computing and distributed intelligence, which can be used in an on demand fashion as a problem-solving resource in many fields of human endeavor-and, in particular, science and engineering. The availability of grid resources will give rise to dramatically new classes of applications, in which computing resources are no longer localized but, rather, distributed, heterogeneous, and dynamic; computation is increasingly sophisticated and multidisciplinary; and computation is integrated into our daily lives and, hence, subject to stricter time constraints than at present. The impact of these new applications will be pervasive, ranging from new systems for scientific inquiry, through computing support for crisis management, to the use of ambient computing to enhance personal mobile computing environments. To realize this vision, significant scientific and technical obstacles must be overcome. Principal among these is usability. The goal of the Grid Application Development Software (GrADS) project is to simplify distributed heterogeneous computing in the same way that the World Wide Web simplified information sharing over the Internet. To that end, the project is exploring the scientific and technical problems that must be solved to make it easier for ordinary scientific users to develop, execute, and tune applications on the Grid. In this paper, the authors describe the vision and strategies underlying the GrADS project, including the base software architecture for grid execution and performance monitoring, strategies and tools for construction of applications from libraries of grid-aware components, and development of innovative new science and engineering applications that can exploit these new technologies to run effectively in grid environments.
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11.
  • Bezbakh, A.A., et al. (författare)
  • Evidence for the First Excited State of H 7
  • 2020
  • Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 124:2
  • Tidskriftsartikel (refereegranskat)abstract
    • The H7 system was populated in the H2(He8,He3)H7 reaction with a 26 AMeV He8 beam. The H7 missing mass energy spectrum, the H3 energy and angular distributions in the H7 decay frame were reconstructed. The H7 missing mass spectrum shows a peak, which can be interpreted either as unresolved 5/2+ and 3/2+ doublet or one of these states at 6.5(5) MeV. The data also provide indications of the 1/2+ ground state of H7 located at 1.8(5) MeV with quite a low population cross section of ∼25 μb/sr within angular range θc.m.≃(17°-27°).
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12.
  • Borcan, C, et al. (författare)
  • First identification of excited states in the N = Z nucleus Br-70
  • 1999
  • Ingår i: EUROPEAN PHYSICAL JOURNAL A. - : SPRINGER VERLAG. ; 5:3, s. 243-246
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Excited states in the T-z = 0 nucleus Br-70 have been investigated using the reaction Ni-58(O-16,1p3n). gamma rays were detected with one EUROBALL CLUSTER detector and three single HPGe detectors. Charged particles and neutrons were registered with the Ro
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13.
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14.
  • Muzalevskii, I. A., et al. (författare)
  • Resonant states in H 7: Experimental studies of the H 2 (He 8, He 3) reaction
  • 2021
  • Ingår i: Physical Review C. - 2469-9985 .- 2469-9993. ; 103:4
  • Tidskriftsartikel (refereegranskat)abstract
    • The extremely neutron-rich system H7 was studied in the direct H2(He8,He3)H7 transfer reaction with a 26 AMeV secondary He8 beam [Bezbakh et al., Phys. Rev. Lett. 124, 022502 (2020)PRLTAO0031-900710.1103/PhysRevLett.124.022502]. The missing mass spectrum and center-of-mass angular distributions of H7, as well as the momentum distribution of the H3 fragment in the H7 frame, were constructed. In addition, we carried out another experiment with the same beam but a modified setup, which was cross-checked by the study of the H2(Be10,He3)Li9 reaction. A solid experimental evidence is provided that two resonant states of H7 are located in its spectrum at 2.2(5) and 5.5(3)MeV relative to the H3+4n decay threshold. Also, there are indications that the resonant states at 7.5(3) and 11.0(3)MeV are present in the measured H7 spectrum. Based on the energy and angular distributions, obtained for the studied H2(He8,He3)H7 reaction, the weakly populated 2.2(5)-MeV peak is ascribed to the H7 ground state. It is highly plausible that the firmly ascertained 5.5(3)-MeV state is the 5/2+ member of the H7 excitation 5/2+-3/2+ doublet, built on the 2+ configuration of valence neutrons. The supposed 7.5-MeV state can be another member of this doublet, which could not be resolved in Bezbakh et al. [Phys. Rev. Lett. 124, 022502 (2020)PRLTAO0031-900710.1103/PhysRevLett.124.022502]. Consequently, the two doublet members appeared in the spectrum of H7 in the work mentioned above as a single broad 6.5-MeV peak.
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15.
  • Nikolskii, E.Y., et al. (författare)
  • H 6 states studied in the H 2 (He 8, He 4) reaction and evidence of an extremely correlated character of the H 5 ground state
  • 2022
  • Ingår i: Physical Review C. - 2469-9993 .- 2469-9985. ; 105:6
  • Tidskriftsartikel (refereegranskat)abstract
    • The extremely neutron-rich system H6 was studied in the direct H2(He8,He4)H6 transfer reaction with a 26A MeV secondary He8 beam. The measured missing mass spectrum shows a broad bump at ≈4-8 MeV above the H3+3n decay threshold. This bump can be interpreted as a broad resonant state in H6 at 6.8(5) MeV. The population cross section of such a presumably p-wave state (or it may be few overlapping states) in the energy range from 4 to 8 MeV is dσ/dωc.m.≃190-80+40μb/sr in the angular range 5°<θc.m.<16°. The obtained missing mass spectrum is practically free of H6 events below 3.5 MeV (dσ/dωc.m. 5μb/sr in the same angular range). The steep rise of the H6 missing mass spectrum at ≈3 MeV allows us to derive the lower limit for the possible resonant-state energy in H6 to be 4.5(3) MeV. According to the paring energy estimates, such a 4.5(3) MeV resonance is a realistic candidate for the H6 ground state (g.s.). The obtained results confirm that the decay mechanism of the H7 g.s. (located at 2.2 MeV above the H3+4n threshold) is the "true"(or simultaneous) 4n emission. The resonance energy profiles and the momentum distributions of fragments of the sequential H6→H5(g.s.)+n→H3+3n decay were analyzed by the theoretically updated direct four-body-decay and sequential-emission mechanisms. The measured momentum distributions of the H3 fragments in the H6 rest frame indicate very strong "dineutron-type"correlations in the H5 ground state decay.
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16.
  • Nikolskii, E.Y., et al. (författare)
  • Study of proton and deuteron pickup reactions (d, 3 He), (d, 4 He) with 8 He and 10 Be radioactive beams at ACCULINNA-2 fragment separator
  • 2023
  • Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 541, s. 121-125
  • Tidskriftsartikel (refereegranskat)abstract
    • The extremely neutron-rich systems 7H, 6H were studied in the 2H(8He, 3He)7H and 2H(8He, 4He)6H proton and deuteron pickup reactions with a 26 AMeV secondary 8He beam produced at the new ACCULINNA-2 fragment separator. In addition, the same proton and deuteron pickup reactions were generated using the 42 AMeV 10Be beam, and the population of low-lying 9Li and 8Li states was measured in reactions 2H(10Be,3He)9Li and 2H(10Be,4He)8Li, respectively. The latter were used as reference measurements in order to check the setup calibration over the excitation energy of 7,6H and to determine the real experimental energy resolution which was compared with Monte Carlo calculations. The corresponding results obtained for the superheavy hydrogen systems 7H, 6H are presented and discussed. Typical excitation spectra of the 9Li and 8Li nuclei are also shown.
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17.
  • Ovejas, J. D., et al. (författare)
  • Halo effects in the low-energy scattering of 15 C with heavy targets
  • 2020
  • Ingår i: Acta Physica Polonica, Series B.. - 1509-5770 .- 0587-4254. ; 51:3, s. 731-736
  • Tidskriftsartikel (refereegranskat)abstract
    • The neutron-rich carbon isotope 15C was postulated to be a halo nucleus (Sn = 1215 keV, S2n = 9395 keV) according to different high-energy experiments. If so, it would be the only halo nucleus exhibiting a "pure" s-wave structure of the ground state. At low collision energies, the effect of this halo structure should manifest as a strong absorption pattern in the angular distribution of the elastic cross section, with a total suppression of the nuclear rainbow due to the large neutron transfer and breakup probabilities, enhanced by the halo configuration. The IS619 experiment, carried out at the HIE-ISOLDE facility at CERN (Switzerland), is the first dynamical study of this nucleus at energies around the Coulomb barrier. It aims to probe the halo structure via the measurement of the elastic cross section on a high-Z 208Pb target. Preliminary results of the elastic cross section are discussed and compared to Optical Model calculations.
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18.
  • Ovejas, J. D., et al. (författare)
  • Study of the scattering of 15C at energies around the Coulomb barrier
  • 2020
  • Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1643:1
  • Konferensbidrag (refereegranskat)abstract
    • The neutron rich carbon isotope 15C is the only known case of an almost "pure"2s1/2 single-neutron halo ground state configuration. At collision energies around the Coulomb barrier the reaction dynamics is expected to be dominated by single neutron transfer and breakup. To investigate these effects, we have measured the scattering of 15C with a 208Pb target at 65 MeV at the HIE-ISOLDE facility in CERN (Geneva, Switzerland). The preliminary data demonstrates the presence of a strong long-range absorption pattern in the angular distribution of the elastic cross section. The results are discussed in the framework of Optical Model calculations.
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19.
  • Pausch, G., et al. (författare)
  • RoSiB - a 4 pi silicon ball for charged-particle detection in EUROBALL
  • 2000
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 443:03-feb, s. 304-318
  • Tidskriftsartikel (refereegranskat)abstract
    • A 4 pi silicon bail for detection and identification of light charged particles in large multidetector gamma-arrays as EUROBALL is presented. The design is based on a N = 42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive material for gamma-rays is minimized to the detector thickness of 300 or 500 mu m and a 0.63 mm ceramic backing. The geometrical coverage is designed for about 90% of 4 pi. A pulse shape discrimination method with totally depleted detectors working in the reverse mount allows identifying protons and alpha-particles above an energy threshold of about 2 MeV. The performances of the ball were rested at the tandem - booster accelerator combination of the MPI Heidelberg in two experiments using the high-recoil reaction of 228 MeV Ni-58 + Ti-46 and the low-recoil reaction of 95 MeV O-16 + Ni-58. The two-dimensional spectra of zero-crossing (ZC) versus energy confirmed an excellent discrimination of protons and alpha-particles in all the detectors at different angles. The energy spectra of protons and alpha-particles measured in the experiments are presented. too. The gamma-spectra measured in coincidence with various combinations of emitted particles showed a high selectivity of the ball. The reduced total efficiency for protons of 59% and 55% and alpha-particles of 44% and 32% measured in a nuclear spectroscopy application is analyzed in a Monte-Carlo simulation (GEANT). It is due to a combined influence of a thick target needed to stop the recoiling residual nuclei and thick absorbers needed to protect the Si-detectors from scattered beam. The results along with the GEANT extrapolation to optimum experimental conditions confirm that RoSiB is a highly efficient and selective device for identification of rare reaction channels with heavy ions.
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20.
  • Távora, V.G., et al. (författare)
  • Strong coupling effects on near-barrier 15C + 208Pb elastic scattering
  • 2024
  • Ingår i: Physics Letters B. - 0370-2693. ; 855
  • Tidskriftsartikel (refereegranskat)abstract
    • The presence of a neutron halo in 15C has been demonstrated in several reaction experiments at intermediate energies. In the present study, the dynamical effects of this structure are observed for the first time at Coulomb barrier energies in the 15C + 208Pb quasi-elastic scattering at MeV, measured at the HIE-ISOLDE facility, CERN using the high-granularity detector array GLORIA. A combined continuum discretised coupled channels and coupled reaction channels calculation describes the data well and significant coupling effects due both to breakup and single-neutron stripping are identified.
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21.
  • Távora, V. G., et al. (författare)
  • Strong coupling effects on near-barrier 15C + 208Pb elastic scattering
  • 2024
  • Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 855
  • Tidskriftsartikel (refereegranskat)abstract
    • The presence of a neutron halo in 15C has been demonstrated in several reaction experiments at intermediate energies. In the present study, the dynamical effects of this structure are observed for the first time at Coulomb barrier energies in the 15C + 208Pb quasi-elastic scattering at Elab=65 MeV, measured at the HIE-ISOLDE facility, CERN using the high-granularity detector array GLORIA. A combined continuum discretised coupled channels and coupled reaction channels calculation describes the data well and significant coupling effects due both to breakup and single-neutron stripping are identified.
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22.
  • Gierlik, M., et al. (författare)
  • Comparative study of large NaI(Tl) and BGO scintillators for the EURopean illicit TRAfficking countermeasures kit project
  • 2005
  • Konferensbidrag (refereegranskat)abstract
    • One of the essential requirements of the Tagged Neutron Inspection System, which is the principle of the EURITRACK project, is an efficient and inexpensive gamma ray detector. For this purpose properties of cylindrical 3"×3" and 5"×5" BGO, and 3"×3", two different 5"×5", and a rectangular 5"×5" ×10" NaI(Tl) scintillators were explored. In this communication we report on light yield, energy and time resolution of the investigated crystals at high energies of γ-rays. Additionally, results of Monte Carlo simulations of the crystals' efficiencies are compared to peak-to-total ratios obtained experimentally for various combinations of PMTs and the scintillators.
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23.
  • Gierlik, M., et al. (författare)
  • Comparative study of large NaI(Tl) and BGO scintillators for the EURopean Illicit TRAfficking Countermeasures Kit project
  • 2006
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 53:3, s. 1737-1743
  • Tidskriftsartikel (refereegranskat)abstract
    • The Tagged Neutron Inspection System, which is the principle of the EURITRACK project, requires efficient and inexpensive gamma-ray detectors. For this purpose, properties of 3 x 3 and 5 x 5 cylindrical BGO and NaI(TI) scintillators and of a 5 x 5 x 10 rectangular NaI(TI) scintillator were determined. 14 Light yield, energy and time resolution of the investigated crystals at the energy of few MeVs of gamma-rays are emphasized. Additionally, the crystals efficiencies calculated with Monte Carlo simulations are compared to peak-to-total ratios obtained experimentally for various combinations of PMTs and the scintillators.
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24.
  • Kapusta, M., et al. (författare)
  • Comparison of the scintillation properties of LSO : Ce manufactured by different laboratories and of LGSO : Ce
  • 2000
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 47:4, s. 1341-1345
  • Tidskriftsartikel (refereegranskat)abstract
    • We measured photoelectron yield, light output, decay times of the light pulses, cerium concentration, energy resolution and time resolution of LSO:Ce manufactured by different laboratories and LGSO:Ce. The LSO samples show excellent scintillation properties: high light output, close to 30,000 ph/MeV and good energy resolution of 7.3% FWHM for Cs-137 gamma-source full energy peak. Time resolution measured in geometry fulfilling the PET scanners requirements is equal to 450 ps. We also present results fi om the measurements with LGSO:Ce by Hitachi Chemical Co., which is of similar chemical composition to LSO. LGSO, at present stage of development, shows about 20% lower light output than LSO and energy resolution of 12.4% FWHM for 662 keV gamma-rays. LSO crystals used in our studies posses similar in scintillation properties, although we suppose that the details of the productions method are different due to the differences in Ce concentration. LGSO is a new and very promising scintillator due to lower background radiation in comparison to LSO, but it features worse energy resolution and smaller number of photoelectrons.
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25.
  • Madder, Ryan D, et al. (författare)
  • Confirmation of the Intracoronary Near-Infrared Spectroscopy Threshold of Lipid-Rich Plaques That Underlie ST-Segment-Elevation Myocardial Infarction.
  • 2016
  • Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1524-4636. ; 36:5, s. 1010-1015
  • Tidskriftsartikel (refereegranskat)abstract
    • In a previous exploratory analysis, intracoronary near-infrared spectroscopy (NIRS) found the majority of culprit lesions in ST-segment-elevation myocardial infarction (STEMI) to contain a maximum lipid core burden index in 4 mm (maxLCBI4mm) of >400. This initial study was limited by a small sample size, enrollment at a single center, and post hoc selection of the maxLCBI4mm ≥400 threshold. This study was designed a priori to substantiate the ability of NIRS to discriminate STEMI culprit from nonculprit segments and to confirm the performance of the maxLCBI4mm ≥400 threshold.
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26.
  • Markenroth, Karin, 1973, et al. (författare)
  • Crossing the dripline to N-11 using elastic resonance scattering
  • 2000
  • Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 6203:3
  • Tidskriftsartikel (refereegranskat)abstract
    • The level structure of the unbound nucleus N-11 has been studied by C-10+p elastic resonance scattering in inverse geometry with the LISE3 spectrometer at GANIL, using a C-10 beam with an energy of 9.0 MeV/ nucleon. An additional measurement was done at the A1200 spectrometer at MSU. The excitation function above the C-10+p threshold has been determined up to 5 MeV. A potential-model analysis revealed three resonance states at energies 1.27(-0.05)(+0.18) MeV (Gamma = 1.44 +/- 0.2 MeV), 2.01(-0.05)(+0.15) MeV (Gamma = 0.84 +/- 0.2 MeV), and 3.75 +/- 0.05 MeV (Gamma = 0.60 +/- 0.05 MeV) with the spin-parity assignments I-pi=1/2+,1/2,-,5/2+, respectively. Hence, N-11 is shown to have a ground state parity inversion completely analogous to its mirror partner Be-11. A narrow resonance in the excitation function at 4.33 +/- 0.05 MeV was also observed and assigned spin parity 3/2-.
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27.
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28.
  • Palacz, M, et al. (författare)
  • Highly efficient charged particle veto detector CUP
  • 2005
  • Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 550:1-2, s. 414-424
  • Tidskriftsartikel (refereegranskat)abstract
    • A novel, highly efficient, plastic scintillator detector has been constructed. The primary application of the detector is to act as a veto device in heavy-ion-induced fusion-evaporation reactions, in which the structure of proton-rich nuclides is investigated by gamma-ray spectroscopy methods. The detector rejects events in which light charged particles, like protons and alpha particles, are emitted in the evaporation process, facilitating selection of reaction channels associated with emission of only neutrons. The detector was used in a EUROBALL experiment, with achieved efficiencies of 80% and 63% for protons and alpha particles, respectively. The design of the detector, its performance and limitations are discussed.
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29.
  • Pausch, G, et al. (författare)
  • RoSiB - a 4 pi silicon ball for charged-particle detection in EUROBALL
  • 2000
  • Ingår i: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV, AMSTERDAM. - 0168-9002. ; 443:2-3, s. 304-318
  • Tidskriftsartikel (refereegranskat)abstract
    • A 4 pi silicon bail for detection and identification of light charged particles in large multidetector gamma-arrays as EUROBALL is presented. The design is based on a N = 42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive
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30.
  • Podsiadlo, P., et al. (författare)
  • Baseline trabecular bone and its relation to incident radiographic knee osteoarthritis and increase in joint space narrowing score : directional fractal signature analysis in the MOST study
  • 2016
  • Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 24:10, s. 1736-1744
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose To explore the association of baseline trabecular bone structure with incident tibiofemoral (TF) osteoarthritis (OA) and with increase in joint space narrowing (JSN) score. Methods The Multicenter Osteoarthritis Study (MOST) includes subjects with or at risk for knee OA. Knee radiographs were scored for Kellgren–Lawrence (KL) grade and JSN at baseline, 30, 60 and 84 months. Knees (KL ≤ 1) at baseline were assessed for incident OA (KL ≥ 2) and increases in JSN score. For each knee image at baseline, a variance orientation transform method (VOT) was applied to subchondral tibial bone regions of medial and lateral compartments. Seventeen fractal parameters were calculated per region. Associations of each parameter with OA incidence and with medial and lateral JSN increases were explored using logistic regression. Analyses were stratified by digitized film (DF) vs computer radiography (CR) and adjusted for confounders. Results Of 894 knees with CR and 1158 knees with DF, 195 (22%) and 303 (26%) developed incident OA. Higher medial bone roughness was associated with increased odds of OA incidence at 60 and 84 months and also, medial and lateral JSN increases (primarily vertical). Lower medial and lateral anisotropy was associated with increased odds of medial and lateral JSN increase. Compared to DF, CR had more associations and also, similar results at overlapping scales. Conclusion Baseline trabecular bone texture was associated with incident radiographic OA and increase of JSN scores independently of risk factors for knee OA. Higher roughness and lower anisotropy were associated with increased odds for radiographic OA change.
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31.
  • Shao, WG, et al. (författare)
  • The SysteMHC Atlas project
  • 2018
  • Ingår i: Nucleic acids research. - : Oxford University Press (OUP). - 1362-4962 .- 0305-1048. ; 46:D1, s. D1237-D1247
  • Tidskriftsartikel (refereegranskat)
  •  
32.
  • Struyf, E., et al. (författare)
  • The Role of Vegetation in the Okavango Delta Silica Sink
  • 2015
  • Ingår i: Wetlands (Wilmington, N.C.). - : Springer Science and Business Media LLC. - 0277-5212 .- 1943-6246. ; 35:1, s. 171-181
  • Tidskriftsartikel (refereegranskat)abstract
    • We assessed the role of vegetation and hydrology in the Si cycle in the Okavango Delta. Our results show a large storage of biogenic Si (BSi) in vegetation and the sediments. The biological storage is among the highest observed so far for any ecosystem worldwide. Floodplain vegetation accumulates similar amounts of BSi in both the temporary floodplains and the permanent floodplains, with most values observed between 20 and 100 g Si m(-2). This vegetation Si, after litterfall, contributes to a large biogenic Si storage in the sediments. In temporary floodplains, sediments contain less BSi (375-1950 g Si m(-2) in the top 5 cm) than in the permanent floodplains (1950-3600 g Si m(-2) in the top 5 cm). BSi concentrations in the floodplain sediments decline exponentially indicating rapid dissolution. In the occasional and seasonal floodplains, unidirectional solute transfer from floodplains to the islands will remove Si from the riverine systems. Our work clearly emphasizes the crucial role of floodplains and wetlands in Si transport through tropical rivers, and the potential interference of hydrology with this role.
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33.
  • Swiderski, L., et al. (författare)
  • Boron-10 loaded BC523A liquid scintillator for neutron detection in the border monitoring
  • 2007
  • Ingår i: 2007 IEEE Nuclear Science Symposium &amp; Medical Imaging Conference. - : IEEE. - 1424409233 - 9781424409235 ; , s. 1389-1395
  • Konferensbidrag (refereegranskat)abstract
    • A BC523A liquid scintillator loaded with boron-10 was tested as a detector for both fast and thermal neutrons. Pulse shape discrimination (PSD) method based on a zero-crossing principle was applied to distinguish between neutron and gamma radiation. High quantum efficiency Photonis XP5500B photomultiplier was used to enhance light detection from the scintillator. This allowed a good registration of the energy spectrum of neutron capture events on boron-10, corresponding to about 60 keVee. The applied PSD method proved to be useful for n/γ discrimination. A good resolving power of the method was achieved even without gating on neutron capture events. A comparison with a standard BC501A liquid scintillator was done to evaluate thermal neutrons detection efficiency in BC523A.
  •  
34.
  • Swiderski, L., et al. (författare)
  • Boron-10 Loaded BC523A Liquid Scintillator for Neutron Detection in the Border Monitoring
  • 2008
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 55:6, s. 3710-3716
  • Tidskriftsartikel (refereegranskat)abstract
    • A BC523A liquid scintillator loaded with boron-10 was tested as a detector for both fast and thermal neutrons. A pulse shape discrimination (PSD) method based on a zero-crossing principle was applied to distinguish between neutron and gamma radiation. High quantum efficiency Photonis XP5500B photomultiplier was used to enhance light detection from the scintillator. This allowed a good registration of the energy spectrum of neutron capture events on boron-10, corresponding to about 60 keV gamma-rays. The applied PSD method proved to be useful for n/gamma discrimination. A good resolving power of the method was achieved even without gating on neutron capture events. A comparison with a standard BC501A liquid scintillator was done to evaluate thermal neutrons detection efficiency in BC523A.
  •  
35.
  • Swiderski, L., et al. (författare)
  • Further Study of Boron-10 Loaded Liquid Scintillators for Detection of Fast and Thermal Neutrons
  • 2010
  • Ingår i: IEEE Transactions on Nuclear Science. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9499 .- 1558-1578. ; 57:1, s. 375-380
  • Tidskriftsartikel (refereegranskat)abstract
    • Boron-10 loaded liquid scintillators were studied in order to improve n/gamma separation. Pulse shape discrimination (PSD) was implemented by means of a zero-crossing (ZC) method to distinguish between gamma-rays and fast/slow neutrons. Significant progress was done for BC523A2 and EJ339A2 scintillators loaded with reduced amount of B-10 (2% and 2.5%, respectively), as compared to the results obtained earlier with BC523A loaded with 4.4% of B-10. The improvement was probably caused by the reduction of B-10 content, as indicated in the reported study. A B-10 loaded scintillator EJ309B5 based on non- flammable liquid was also studied, showing the best separation of thermal neutron capture events from fast neutrons, gamma-rays and noise.
  •  
36.
  • Swiderski, L., et al. (författare)
  • Further study of Boron-10 loaded liquid scintillators for detection of fast and thermal neutrons
  • 2008
  • Konferensbidrag (refereegranskat)abstract
    • Boron-10 loaded liquid scintillators were studied in order to improve n/γ separation. Pulse shape discrimination (PSD) was done by means of a zero-crossing (ZC) method to distinguish between γ-rays and fast/slow neutrons. A significant progress was achieved for BC523A2 and EJ339A2 loaded with reduced amount of ,10B (2% and 2.5%, respectively), as compared to the results obtained earlier with BC523A loaded with 5% of 10B. The improvement was probably caused by the reduction of 10B content, as indicated in the latter study. A 10B loaded scintillator EJ309B5 based on a non-flammable liquid was also studied, showing the best separation of thermal neutron capture events from fast neutrons, γ-rays and noise.
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