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Search: L773:2101 6275 OR L773:2100 014X OR L773:9782759819706 > (2010-2014)

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1.
  • Alberdi, Antxon, et al. (author)
  • The jet of the Low Luminosity AGN of M81. Evidence of Precession
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 61
  • Conference paper (peer-reviewed)abstract
    • In this contribution, we summarize our main results of a big campaign of global VLBI observations of the AGN in M81 (M81*) phase-referenced to the radio supernova SN 1993J. Thanks to the precise multi-epoch and multi-frequency astrometry, we have determined the normalized core-shift of the relativistic jet of M81* and estimated both the magnetic field and the particle density at the jet base. We have also found evidence of jet precession in M81* coming from the systematic time evolution of the jet orientation correlated with changes in the overall flux density.
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2.
  • Babaahmadi, Arezou, 1985, et al. (author)
  • Electrochemical migration technique to accelerate ageing of cementitious materials
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9782759810468 ; 56
  • Conference paper (peer-reviewed)abstract
    • Durability assessment of concrete structures for constructions in nuclear waste repositories requires long term service life predictions. As deposition of low and intermediate level radioactive waste (LILW) takes up to 100 000 years, it is necessary to analyze the service life of cementitious materials in this time perspective. Using acceleration methods producing aged specimens would decrease the need of extrapolating short term data sets. Laboratory methods are therefore, needed for accelerating the ageing process without making any influencing distortion in the properties of the materials. This paper presents an electro-chemical migration method to increase the rate of calcium leaching from cementitious specimens. This method is developed based on the fact that major long term deterioration process of hardened cement paste in concrete structures for deposition of LILW is due to slow diffusion of calcium ions. In this method the cementitious specimen is placed in an electrochemical cell as a porous path way through which ions can migrate at a rate far higher than diffusion process. The electrical field is applied to the cell in a way to accelerate the ion migration without making destructions in the specimen's micro and macroscopic properties. The anolyte and catholyte solutions are designed favoring dissolution of calcium hydroxide and compensating for the leached calcium ions with another ion like lithium.
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3.
  • Bensby, Thomas, et al. (author)
  • Chemical constraints on the formation of the Galactic thick disk
  • 2012
  • In: Assembling the Puzzle of the Milky Way. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 19
  • Conference paper (peer-reviewed)abstract
    • We highlight some results from our detailed abundance analysis study of 703 kinematically selected F and G dwarf stars in the solar neighbourhood. The analysis is based on spectra of high-resolution (R = 45 000 to 110 000) and high signal-to-noise (S/N approximate to 150 to 300). The main findings include: (1) at a given metallicity, the thick disk abundance trends are more alpha-enhanced than those of the thin disk; (2) the metal-rich limit of the thick disk reaches at least solar metallicities; (3) the metal-poor limit of the thin disk is around [Fe/H] approximate to -0.8; (4) the thick disk shows an age-metallicity gradient; (5) the thin disk does not show an age-metallicity gradient; (6) the most metal-rich thick disk stars at [Fe/H] approximate to 0 are significantly older than the most metal-poor thin disk stars at [Fe/H] approximate to -0.7; (7) based on our elemental abundances we find that kinematical criteria produce thin and thick disk stellar samples that are biased in the sense that stars from the low-velocity tail of the thick disk are classified as thin disk stars, and stars from the high-velocity tail of the thin disk are classified as thick disk stars; (8) age criteria appears to produce thin and thick disk stellar samples with less contamination.
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4.
  • Bijnens, Johan, et al. (author)
  • The hadronic light-by-light contribution to the muon anomalous magnetic moment and renormalization group for EFT
  • 2012
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 37
  • Journal article (peer-reviewed)abstract
    • We give a short overview of the theory of the muon anomalous magnetic moment with emphasis on the hadronic light-by-light and the pion loop contribution. We explain the difference between the hidden local symmetry and full VMD pion loop and discuss leading logarithms in the anomalous sector of 2-flavour chiral perturbation theory.
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5.
  • Bovo, Mirko, 1979, et al. (author)
  • Measurements of a single pulse impinging jet. A CFD reference
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9788026053750 ; 67
  • Conference paper (peer-reviewed)abstract
    • This paper reports three sets of measurements of a single pulse impinging jet. The purpose is to serve as a reference for CFD validation. A gas injector generates a single pulse jet at Re ~90000. The jet impinges on a temperature controlled flat target at different angles (0̈, 30̈, 45̈ and 60̈). The jet velocity field is measured with PIV. The evolution of the jet velocity profile in time is reported at two different locations (suitable as CFD inlet conditions). At the same locations also turbulence quantities are reported. The impingement wall temperature is measured with fast responding thermocouples and infrared camera. These give high time and space resolution respectively. Results are reported in a format suitable for comparison with CFD simulations. The results show that the heat transfer effects are highest for the jet impinging normally on the target. Target inclination has remarkable effects on the jet penetration rate and repeatability. Even small target inclinations result creates a preferential direction for the jet flow and cause a shift in the position of the stagnation region.
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6.
  • Broeg, C., et al. (author)
  • CHEOPS: A transit photometry mission for ESA's small mission programme
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9782759809851 ; 47
  • Conference paper (peer-reviewed)abstract
    • Ground based radial velocity (RV) searches continue to discover exoplanets below Neptune mass down to Earth mass. Furthermore, ground based transit searches now reach milli-mag photometric precision and can discover Neptune size planets around bright stars. These searches will find exoplanets around bright stars anywhere on the sky, their discoveries representing prime science targets for further study due to the proximity and brightness of their host stars. A mission for transit follow-up measurements of these prime targets is currently lacking. The first ESA S-class mission CHEOPS (CHaracterizing ExoPlanet Satellite) will fill this gap. It will perform ultra-high precision photometric monitoring of selected bright target stars almost anywhere on the sky with sufficient precision to detect Earth sized transits. It will be able to detect transits of RV-planets by photometric monitoring if the geometric configuration results in a transit. For Hot Neptunes discovered from the ground, CHEOPS will be able to improve the transit light curve so that the radius can be determined precisely. Because of the host stars' brightness, high precision RV measurements will be possible for all targets. All planets observed in transit by CHEOPS will be validated and their masses will be known. This will provide valuable data for constraining the mass-radius relation of exoplanets, especially in the Neptune-mass regime. During the planned 3.5 year mission, about 500 targets will be observed. There will be 20% of open time available for the community to develop new science programmes.
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7.
  • Chakraborty, S., et al. (author)
  • Ground-state configuration of neutron-rich Aluminum isotopes through Coulomb breakup
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
  • Conference paper (peer-reviewed)abstract
    • Neutron-rich 34,35Al isotopes have been studied through Coulomb excitation using LAND-FRS setup at GSI, Darmstadt. The method of invariant mass analysis has been used to reconstruct the excitation energy of the nucleus prior to decay. Comparison of experimental CD cross-section with direct breakup model calculation with neutron in p3/2 orbital favours 34Al(g.s) - νp3/2 as ground state configuration of 35Al. But ground state configuration of 34Al is complicated as evident from γ-ray spectra of 33Al after Coulomb breakup of 34Al. © Owned by the authors, published by EDP Sciences, 2014.
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8.
  • Cubero, M., et al. (author)
  • Scattering of 9Li on 208Pb at energies around the Coulomb barrier
  • 2011
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9782759806935 ; 17, s. Art. no. 16002-
  • Conference paper (peer-reviewed)abstract
    • In order to study the dynamics of 11Li and 9Li beams in a strong electric field at energies around the Coulomb barrier, we measured at the ISACII-TRIUMF Facility the angular distribution of elastic and inelastic scattering of 11Li+208Pb at 24.2 and 29.7 MeV and 9Li+208Pb at 24, 29.5 and 33 MeV laboratory energies. We present here the first determination of the angular distribution of the cross section of 9Li+208Pb. The results are compared with theoretical calculations using the double-folding São Paulo Potential (SPP) for the real part and a for the imaginary part a Woods-Saxon potential. A good overall agreement is obtained.
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9.
  • del Rio, J. S., et al. (author)
  • CEPA: A LaBr 3 (Ce)/LaCl 3 (Ce) phoswich array for simultaneous detection of protons and gamma radiation emitted in reactions at relativistic energies
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
  • Conference paper (peer-reviewed)abstract
    • A prototype CEPA4, made of four optically isolated phoswich-crystals of LaBr3(Ce)+LaCl3(Ce) packed together in one can of Al, was tested with high energy protons (70-230 MeV) at the cyclotron of Krakow. Further, the response to different gamma radiation standard sources and cosmic muons was determined. Shape analysis of the pulses derived from the four individually coupled PM-tubes was performed and were used as input functions for Monte Carlo simulations in order to simulate the efficiencies and resolutions of a final detector design consisting of 750 such phoswich crystals arranged in a cylindrical disc. © Owned by the authors, published by EDP Sciences, 2014.
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10.
  • Dostal, Jakub, et al. (author)
  • Fast Exciton Dynamics and Coherent Oscillations Revealed by Coherent 2D Spectroscopy in Chlorosomes
  • 2013
  • In: XVIIITH International Conference on Ultrafast Phenomena. - : EDP Sciences. - 2100-014X .- 2101-6275. ; 41
  • Conference paper (peer-reviewed)abstract
    • In this study ultrafast energy transfer dynamics in chlorosomes from sulphur bacterium Chlorobaculum tepidum were explored by means of coherent electronic two-dimensional spectroscopy. Observed sub-100 fs dynamics were attributed to incoherent downhill excitation diffusion between disordered domains within chlorosomes. At the same time vibrational coherent oscillations were investigated on the longer timescales.
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11.
  • El-Alti, Mohammad, 1981, et al. (author)
  • Experimental and computational studies of active flow control on a model truck-trailer
  • 2012
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 25:01012, s. pp 16-
  • Conference paper (peer-reviewed)abstract
    • Active flow control is probably the most challenging research area in vehicle aerodynamics. Being able to manipulate a flow field in order to achieve desired results beneficial to engineering is the only way to meet today’s demands for competitive and efficient solutions in the automotive industry. The current work studies the flow control on a semi detailed model truck by using detached-eddy simulations and wind tunnel experiments aiming at reducing the aerodynamic drag. This study combines both passive and active flow control applied on the rear end of the trailer. An indigenous fluidic actuator (loudspeaker in cavity with slots) is used as a synthetic jet in the experiment. Both experiments and computations demonstrate that the active flow control works successfully and results in flow reattachment to the flaps. The numerical simulations show that the drag coefficient, CD decreased by 3.9% when AFC was activated compared to the baseline case without flaps. The corresponding decrease when AFC was deactivated (with flaps) was only 0.7%. The experimental results show a decrease of CD by 3.1% for the case with activated AFC compared to the baseline case. When AFC was deactivated the corresponding decrease in CD was 1.8%. A detailed flow analysis made in computations and experiments is used to explain these results.
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12.
  • Feltzing, Sofia, et al. (author)
  • The chemical evolution of the Galactic Bulge seen through micro-lensing events
  • 2012
  • In: Assembling the Puzzle of the Milky Way. - : EDP Sciences. - 2100-014X .- 2101-6275. ; 19
  • Conference paper (peer-reviewed)abstract
    • Galactic bulges are central to understanding galaxy formation and evolution. Here we report on recent studies using micro-lensing events to obtain spectra of high resolution and moderately high signal-to-noise ratios of dwarf stars in the Galactic bulge. Normally this is not feasible for the faint turn-off stars in the Galactic bulge, but micro-lensing offers this possibility. Elemental abundance trends in the Galactic bulge as traced by dwarf stars are very similar to those seen for dwarf stars in the solar neighbourhood. We discuss the implications of the ages and metallicity distribution function derived for the micro-lensed dwarf stars in the Galactic bulge.
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13.
  • Floderus, Anders (author)
  • Searches for direct supersymmetric gaugino and slepton pair production in final states with leptons with the ATLAS detector
  • 2013
  • In: HCP 2012 - Hadron Collider Physics Symposium 2012. - : EDP Sciences. - 2100-014X .- 2101-6275. ; 49, s. 15008-15008
  • Conference paper (peer-reviewed)abstract
    • A search for direct production of supersymmetric gauginos and sleptons in final states with two and three leptons is presented. The two lepton analysis uses 4.7 fb(-1) of proton-proton collision data at root s = 7 TeV, while the three lepton analysis uses 13 fb(-1) at root s = 8 TeV. All data were recorded by the ATLAS detector at the Large Hadron Collider. The results are interpreted in the phenomenological minimal supersymmetric Standard Model, as well as simplified models. No significant excess above the Standard Model expectation is observed. Limits on the particle masses are placed at the 95% confidence level. In simplified models, chargino masses are excluded up to 580 GeV.
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14.
  • Fomichev, A. S., et al. (author)
  • Recent results related to excited states of 6Be and 10He
  • 2012
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 38, s. Art. no. 15002-
  • Conference paper (peer-reviewed)abstract
    • The 1H(6Li,6Be)n charge-exchange reaction and the 3H(8He, p)10He two-neutron transfer reaction were recently carried out at the ACCULINNA fragment separator (FLNR, Dubna) to populate the ground and excited states of 6Be and 10He nuclei, respectively. The 6Be ET spectrum (ET is the 6Be energy above its 4He+p+p decay threshold) was obtained with high statistics and described by the well-known 0+ ground state of 6Be at ET = 1.37 MeV, the 2+ state at ET = 3.05 MeV and a broad structure extending from 4 to 16 MeV which could be interpreted as the isovector soft dipole mode associated with the 6Li ground state. In the 10He case the 0+ ground state was found at about 2.1(2) MeV (T ∼ 2 MeV) above the 8He+n+n breakup threshold. Angular correlations observed for 10He decay products show prominent interference patterns allowing to draw conclusions about the structure of low-energy excited states: 1- (E T ∼ 5 MeV) and 2+ (ET > 6 MeV).
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15.
  • Forsberg, Ulrika, et al. (author)
  • Spectroscopic Tools Applied to Element Z = 115 Decay Chains
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X .- 2101-6275. - 9782759811755 - 9782759811762 ; 66, s. 02036-02036
  • Conference paper (peer-reviewed)abstract
    • Nuclides that are considered to be isotopes of element Z = 115 were produced in the reaction 48Ca + 243Am at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt. The detector setup TASISpec was used. It was mounted behind the gas-filled separator TASCA. Thirty correlated α-decay chains were found, and the energies of the particles were determined with high precision. Two important spectroscopic aspects of the offline data analysis are discussed in detail: the handling of digitized preamplified signals from the silicon strip detectors, and the energy reconstruction of particles escaping to upstream detectors relying on pixel-by-pixel dead-layer thicknesses.
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16.
  • Henning, G., et al. (author)
  • Exploring the stability of super heavy elements: First measurement of the fission barrier of 254No
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
  • Conference paper (peer-reviewed)abstract
    • The gamma-ray multiplicity and total energy emitted by the heavy nucleus 254No have been measured at 2 different beam energies. From these measurements, the initial distributions of spin I and excitation energy E * of 254No were constructed. The distributions display a saturation in excitation energy, which allows a direct determination of the fission barrier. 254No is the heaviest shell-stabilized nucleus with a measured fission barrier. © Owned by the authors, published by EDP Sciences, 2014.
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17.
  • Krupko, S. A., et al. (author)
  • The status of new fragment separator ACCULINNA-2 project and the first day experiments
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
  • Conference paper (peer-reviewed)abstract
    • The new facility fragment separator ACCULINNA-2 will be put into operation at the beginning of 2015 in FLNR JINR. The new separator is destined to add considerably to the studies of drip-line nuclei performed with the use of variety of direct reactions known to be distinctive to the 15 - 50 MeV/amu exotic secondary RIBs. Intense beams provided by the U-400M cyclotron will ensure the achievement of this objective. In addition to the RIB separation accomplished by means of the dipole-wedge-dipole selection, the addition of a zero-degree dipole magnet setup is foreseen. A long (13 m) straight section will provide precise time-of-flight measurements. © Owned by the authors, published by EDP Sciences, 2014.
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18.
  • Lenngren, Nils, et al. (author)
  • Multiexciton Absorption Cross Sections of CdSe Nanocrystals at Band-Edge Energy
  • 2013
  • In: XVIIIth International Conference On Ultrafast Phenomena. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 41
  • Conference paper (peer-reviewed)abstract
    • Picosecond transient absorption signals of two kinds of cadmium selenide quantum dots were measured at various excitation intensities. The average number of excitons per quantum dot was calculated from a Poisson model, which together with kinetic parameters was used to determine exciton population kinetics. Exciton and multiexciton absorption cross sections were determined and analyzed in terms of the electronic states of the quantum dots.
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19.
  • Niebles Atencio, Bercelay, 1979, et al. (author)
  • An experimental study on laminar-turbulent transition at high free-stream turbulence in boundary layers with pressure gradients
  • 2012
  • In: The European Physical Journal Conferences. - : EDP Sciences. ; 25, s. Art. no. 01012-
  • Conference paper (peer-reviewed)abstract
    • We report here the results of a study on measurements and prediction of laminar-turbulenttransition at high free-stream turbulence in boundary layers of the airfoil-like geometries with presence of the external pressure gradient changeover. The experiments are performed for a number of flow cases with different flow Reynolds number, turbulence intensity and pressure gradient distributions. The results were then compared to numerical calculations for same geometries and flow conditions. The experiments and computations are performed for the flow parameters which are typical for turbomachinery applications and the major idea of the current study is the validation of the turbulencemodel which can be used for such engineering applications.
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20.
  • Oberstedt, S., et al. (author)
  • Prompt fission γ -rays from the reactions 252Cf(SF) and 235U(nth, f) - New data
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 62, s. Art. no. 02003-
  • Conference paper (peer-reviewed)abstract
    • We present new spectral data of prompt γ-ray emission from the spontaneous fission of 252Cf. This work was performed in direct response to an OECD/NEA high priority data request. We discuss the impact of our new data on evaluated nuclear data tables not only for this nuclide, but also for 238U and 241Pu, which are always produced in a reactor. Furthermore, we will show results from our investigation of prompt γ-ray emission from the reaction 235 U(nth, f), measured in at the Centre for Energy Research of the Hungarian Academy of Sciences in Budapest, Hungary. Spectral data obtained with three different detectors are consistent and led to an uncertainty on total energy and multiplicity considerably smaller than requested by the OECD/NEA.
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21.
  • Oxfall, Mikael, et al. (author)
  • Moisture levels and drying potential of the concrete in Swedish reactor containments
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X .- 2101-6275. ; 56, s. 1-03002
  • Conference paper (peer-reviewed)abstract
    • The climatic conditions inside nuclear reactor containments are continuously monitored by the plant owners in order to e.g. maintain a suitable climate for the mechanical and electrical equipment. Due to the high temperatures, during operation, the concrete within the containment may act as a moisture source contributing to the humidity. To evaluate if, and to what extent, the concrete inside the containment influences the climatic conditions, the moisture distribution has to be determined. In order to do this, a measurement setup has been developed and tested. The results showed that the measurement setup was suitable for long term measurements of internal relative humidity in concrete. However, measurements close to the concrete surfaces showed tendencies of leakage, increasing the uncertainties of those measurements. The measurement setup was installed at three reactor containments in Sweden during the summer of 2012. Results from the monitoring campaign on one of the three reactor containments are presented in this paper. The results showed that the concrete was still drying after 30-35 years of exposure inside the containment.
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22.
  • Palecek, David, et al. (author)
  • Oscillatory Dynamics in Bacterial Reaction Centres Studied by Electronic 2D Spectroscopy
  • 2013
  • In: XVIIIth International Conference On Ultrafast Phenomena. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 41
  • Conference paper (peer-reviewed)abstract
    • Coherent dynamics in bacterial reaction centres were studied by electronic 2D spectroscopy at 80 K temperature. Polarization measurements together with Fourier analysis allowed assignment of observed population time beatings at different frequencies to the coherences of electronic and vibrational character.
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23.
  • Papadimitriou, G., et al. (author)
  • The No core gamow shell model for ab-initio nuclear structure calculations
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
  • Conference paper (peer-reviewed)abstract
    • We apply the Berggren basis in a No-Core Shell Model framework to calculate ground state (g.s.) energies of 3H, 4He and 5He. In our studies we use the Argonne υ18 and the chiral N3LO potentials, both of which are renormalized via a V low-k process. © Owned by the authors, published by EDP Sciences, 2014.
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24.
  • Pellereau, E., et al. (author)
  • SOFIA: An innovative setup to measure complete isotopic yield of fission fragments
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 62
  • Conference paper (peer-reviewed)abstract
    • We performed an experiment dedicated to the accurate isotopic yield measurement of fission fragments over the whole range. SOFIA exploits the inverse kinematics technique: using heavy ion beams at relativistic energies, fission is induced by Coulomb excitation in a high-Z target. The fragments are emitted forward and both of them are identified in charge and mass. The setup will be presented, as well as preliminary spectra. © Owned by the authors, published by EDP Sciences, 2013.
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25.
  • Pitz-Paal, R., et al. (author)
  • Concentrating solar power in Europe, the Middle East and North Africa: Achieving its potential
  • 2012
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 33
  • Conference paper (peer-reviewed)abstract
    • Concentrating solar power (CSP) is a commercially available renewable energy technology capable of harnessing the immense solar resource in Southern Europe, the Middle East and North Africa (the MENA region), and elsewhere. This paper summarises the findings of a study by the European Academies Science Advisory Council which has examined the current status and development challenges of CSP, and consequently has evaluated the potential contribution of CSP in Europe and the MENA region to 2050. It identifies the actions that will be required by scientists, engineers, policy makers, politicians, business and investors alike, to enable this vast solar resource to make a major contribution to establishing a sustainable energy system. The study concludes that cost reductions of 50-60% in CSP electricity may reasonably be expected in the next 10-15 years, enabling the technology to be cost competitive with fossil-fired power generation at some point between 2020 and 2030. Incorporation of storage delivers added value in enabling CSP to deliver dispatchable power. Incentive schemes will be needed in Europe and MENA countries to enable this point to be achieved. Such schemes should reflect the true value of electricity to the grid, effectively drive R&D, and ensure transparency of performance and cost data.
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26.
  • Rahaman, A., et al. (author)
  • Study of ground state wave-function of the Neutron-rich 29,30Na isotopes through coulomb breakup
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
  • Conference paper (peer-reviewed)abstract
    • Coulomb breakup of unstable neutron rich nuclei 29,30Na around the 'island of inversion' has been studied at energy around 434 MeV/nucleon and 409 MeV/nucleon respectively. Four momentum vectors of fragments, decay neutron from excited projectile and γ-rays emitted from excited fragments after Coulomb breakup are measured in coincidence. For these nuclei, the low-lying dipole strength above one neutron threshold can be explained by direct breakup model. The analysis for Coulomb breakup of 29,30Na shows that large amount of the cross section yields the 28Na, 29Na core in ground state. The predominant ground-state configuration of 29,30Na is found to be 28Na(g.s) νs1/2 and 29Na(g.s) νs1/2,respectively. © Owned by the authors, published by EDP Sciences, 2014.
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27.
  • Rodriguez-Sanchez, J. L., et al. (author)
  • Fission of highly excited nuclei investigated in complete kinematic measurements
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 62
  • Conference paper (peer-reviewed)abstract
    • Fission is an extremely complex mechanism that requires a dynamical approach to describe the evolution of the process in terms of intrinsic and collective excitations of the nuclear constituents. In order to determine these effects a complex experimental setup was mounted at GSI, which allowed us for the first time the full identification in charge and mass of all fission fragments thanks to a magnetic separation and the use of the inverse kinematic technique. Moreover, we also measured the neutron multiplicities and the light-charged particles emitted in coincidence with fission. These complete kinematic measurements will be used to define sensitive observables to dissipative and transient effects in fission. In this manuscript we present the first results for the total fission cross sections. © Owned by the authors, published by EDP Sciences, 2013.
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28.
  • Rojo, Borja, 1989, et al. (author)
  • Experimental heat transfer study of Endwall in a linear cascade with IR thermography
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9788026053750 ; 67
  • Conference paper (peer-reviewed)abstract
    • This abstract presents an endwall heat transfer experimental data of air flow going through outlet guide vanes (OGVs) situated in a low speed linear cascade. The measurement technique for this experiment was infrared thermography. In order to calculate the heat transfer coefficient (HTC) on the endwall, it has been used an instrumented window with a controlled constant temperature in one side of a 5 millimeter Plexiglass in order to generate high temperature gradients and, therefore, by measuring the surface temperature one the other side of the Plexiglass, it is calculated the HTC. Due to the fact that Plexiglass material has not good optical properties at infrared spectrum, it has been used a thin layer of black paint (10-12 μm) which has high emissivity (0.973) in the range of temperature that we are working. The Reynolds number for this experiment is 300000 in on and off-design configuration of the OGVs (on-design 25° and off-design cases are 40° and-25° incident angle). Furthermore, the on-design case is run at two different Reynolds number, 300000 and 450000. During this experiments it can be seen how changing the inlet angle to the OGVs produces significant differences on the heat transfer along the endwall. The main objective for this investigation is to study the heat transfer along the endwall of a linear cascade so that it would be a well-defined test case for CFD validation.
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29.
  • Ros, Katrin (author)
  • Pebble formation by ice condensation
  • 2013
  • In: Instabilities And Structures In Proto-Planetary Disks. - : EDP Sciences. - 2100-014X .- 2101-6275. ; 46
  • Conference paper (peer-reviewed)abstract
    • Pebbles with sizes of centimeters to decimeters are needed in order to form kilometer-sized planetesimals, which in turn are needed for planet formation to proceed. The well-studied mechanism of coagulation is efficient only up to millimeter-sized dust grains. In this proceeding a numerical model of ice condensation as a complementary growth mechanism in turbulent protoplanetary discs is discussed. Close to an ice line, particles grow efficiently by ice condensation, which, combined with radial mixing, can supply a large extent of the disc with icy pebbles. Growth from millimeter-sized dust grains to at least decimeter-sized pebbles is possible on a time scale of only 10 000 years. The resulting particles are large enough to enable further growth into planetesimals via a variety of particle concentration mechanisms and subsequent gravitational collapse.
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30.
  • Schröder, Bent (author)
  • The tagged photon facility at the MAX IV Laboratory
  • 2014
  • In: INPC 2013 - International Nuclear Physics Conference, Vol. 2. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66, s. 11035-11035
  • Conference paper (peer-reviewed)abstract
    • The upgraded tagged photon facility at the MAX IV Laboratory is presented. The pulsed electron beam from a linac system is stretched in the MAX I ring and the electron beam hits a thin aluminium foil in which bremsstrahlung is produced. One of two available magnetic spectrometers is used to determine the energy of the post-bremsstrahlung electrons. The tagged photon ranges from 10 to 180 MeV with an energy resolution of about 300 keV. Rates as high as 4x10(6) photons s(-1) MeV-1 have been used. The experimental area and facilities are described as well as examples of ongoing experiments.
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31.
  • Wamers, F., et al. (author)
  • Exclusive measurements of nuclear breakup reactions of 17Ne
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 66
  • Conference paper (peer-reviewed)abstract
    • We have studied one-proton-removal reactions of about 500MeV/u 17Ne beams on a carbon target at the R3B/LAND setup at GSI by detecting beam-like 15O-p and determining their relative-energy distribution. We exclusively selected the removal of a 17Ne halo proton, and the Glauber-model analysis of the 16F momentum distribution resulted in an s2 contribution in the 17Ne ground state of about 40%. © Owned by the authors, published by EDP Sciences, 2014.
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32.
  • Wilson, J.N., et al. (author)
  • LICORNE: A new and unique facility for producing intense, kinematically focused neutron beams at the IPN Orsay
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 62, s. Art. no. 05006-
  • Conference paper (peer-reviewed)abstract
    • LICORNE is a new neutron source recently installed at the tandem accelerator of the Institut de Physique Nucléaire d'Orsay, where a Li7-beam is used to bombard a hydrogen-containing target to produce an intense forward-directed neutron beam. The directionality of the beam, which is the unique characteristic of LICORNE, will permit the installation of γ-ray detectors dedicated to the investigation of fission fragment de-excitation which are unimpeded by neutrons from the source. A first experimental program will focus on the measurement of prompt γ-ray emission in the neutron-induced fission of fertile and fissile isotopes at incident neutron energies relevant for the core design of Generation-IV nuclear reactors. Other potential uses of the LICORNE facility for both fundamental and applied physics research are also presented.
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33.
  • Atomassa, Ermias, et al. (author)
  • Feasibility studies for nucleon structure measurements with PANDA
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 81
  • Journal article (peer-reviewed)abstract
    • The study of nucleon structure is one of the main physics goals of PANDA to be built at the FAIR accelerator complex. The excellent particle identification performance of the PANDA detector will enable measurements of exclusive channels p̄ p -> e^+e^- and p̄ p -> pi^0 J/psi -> pi^0e^+e^- to extract the electromagnetic form factors of protons and pi-nucleon Transition Distribution Amplitudes (pi-N TDAs). After a brief description of the PANDA apparatus and a method to handle momentum resolution degradation due to Bremsstrahlung, the physics of pi-N TDAs is discussed. An estimate for the expected signal to background ratio for p̄ p -> pi^0 J/psi -> pi^0e^+e^- that takes into account the main background source is given.
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34.
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35.
  • Butkus, Vytautas, et al. (author)
  • Phase relationships of spectral oscillations in 2D molecular spectroscopy
  • 2013
  • In: 18th International Conference on Ultrafast Phenomena, UP 2012. - : EDP Sciences. - 9782759809561 ; 41
  • Conference paper (peer-reviewed)abstract
    • Spectral oscillations in 2D molecular spectroscopy of the displaced oscillator system and their phase relationships are analyzed. The phase maps of the dispersive and absolute-valued signals give hints for experimental probing of peak oscillations.
  •  
36.
  • D'Ammando, F., et al. (author)
  • Relativistic jets in narrow-line Seyfert 1 galaxies. New discoveries and open questions
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; , s. 05006-
  • Conference paper (peer-reviewed)abstract
    • Before the launch of the Fermi satellite only two classes of AGNs were known to produce relativistic jets and thus emit up to the γ-ray energy range: blazars and radio galaxies, both hosted in giant elliptical galaxies. The first four years of observations by the Large Area Telescope on board Fermi confirmed that these two are the most numerous classes of identified sources in the extragalactic γ-ray sky, but the discovery of γ-ray emission from 5 radio-loud narrow-line Seyfert 1 galaxies revealed the presence of a possible emerging third class of AGNs with relativistic jets. Considering that narrow-line Seyfert 1 galaxies seem to be typically hosted in spiral galaxy, this finding poses intriguing questions about the nature of these objects, the onset of production of relativistic jets, and the cosmological evolution of radio-loud AGN. Here, we discuss the radio-to-γ-rays properties of the γ-ray emitting narrow-line Seyfert 1 galaxies, also in comparison with the blazar scenario.
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37.
  • Destefanis, Marco, et al. (author)
  • Spin studies via Drell-Yan processes at PANDA
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 73
  • Journal article (peer-reviewed)abstract
    • The nucleon structure is still not completely understood. A transverse momentum dependent description of the nucleon structure is a crucial milestone for several forthcoming studies in a wide range of experimental scenarios. By means of antiproton beams, possibly polarized in a later stage of the project, with a beam momentum up to 15 GeV/c, which will be available at the future FAIR facility, the nonperturbative region of QCD is planned to be investigated. One of the main goals of the forthcoming experiments at FAIR is the study of Drell-Yan lepton pairs by means of proton-antiproton annihilations, taking also advantage of the expected high luminosity. The Drell-Yan production is a unique tool to access the spin dependent properties of the nucleon, and in particular its transverse degrees of freedom. Transverse Momentum Dependent (TMD) Parton Distribution Functions (PDFs), i.e. the Boer-Mulders function, the Sivers function, and the Transversity, could be deeply investigated by means of experimental angular asymmetries. In later stages of FAIR, single- and double-spin asymmetries could be investigated as well. The Drell-Yan physics program which could be accessed at FAIR with the PANDA experiment will be discussed in details, in the light of existing results in the field.
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38.
  • Gottardo, A., et al. (author)
  • New Isomers in the Neutron-Rich Region Beyond 208Pb
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. - 9782759811755 - 9782759811762 ; 66, s. 02043-02043
  • Conference paper (peer-reviewed)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.
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39.
  • Iazzi, Felice, et al. (author)
  • Doubly strange system physics with antiprotons at PANDA
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 71
  • Journal article (peer-reviewed)abstract
    • The study of the doubly strange hyper-systems represents a step forward in understanding the unexplored world of the strange matter in the frame of a better knowledge of the hyperon-nucleon and hyperon-nucleus interaction. The production of double hyper-systems, up to now, have been based on the use of kaon beams through a double strangeness exchange reaction. A new technique has been designed by the PANDA Collaboration, which will use the antiprotons at 3 GeV/c of the HESR facility at FAIR to create doubly strange hyperons and drive them into nuclear targets. This technique requires the use of 2 targets, located inside and outside the beam pipe. In spite of the constraints arising from the presence of a solid target inside an antiproton ring, the technique looks promising in terms of rate of hyperons and hyper-nuclei produced. After a review of the physics items that will be investigated in the hyper-nuclear section of PANDA experiment, the characteristics of the antiprotons facility, the results of the feasibility study of the 2-target technique, the design of the hyper-nuclear set-up in PANDA and the expected rates of the double hyper-nuclei will be presented.
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40.
  • Leitner, Torsten, 1979-, et al. (author)
  • Coherent wave packet dynamics in photo-excited Nal
  • 2013
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. - 9782759809561 ; 41, s. 02027-
  • Journal article (other academic/artistic)abstract
    • Time and energy resolved photoelectron distributions of photo-excited Nal are presented. A splitting in the photo-excited state suggested by calculations of the intramolecular potential energy surfaces could be confirmed experimentally for the first time.
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41.
  • Leupold, Stefan, et al. (author)
  • Vector-meson dominance revisited
  • 2012
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. ; 37, s. 05008-
  • Journal article (other academic/artistic)
  •  
42.
  • Nishida, Masahiro, et al. (author)
  • Determination of dynamic material properties for poly(L-lactic acid)/poly(e-caprolactone) blends : Experiments and simulation using split Hopkinson pressure bars
  • 2012
  • In: EPJ Web of Conferences. - Les Ulis : EDP Sciences. - 2100-014X. - 9782759807574 ; , s. 3001-
  • Conference paper (peer-reviewed)abstract
    • Coefficients of Cowper-Symonds constitutive equation for PLLA/PCL = 80/20 were determined using the results of compressive tests at high and low strain rates. The simulation of split Hopkinson pressure bar using the coefficients was carried out under the same condition as the experiments. The diameter and thickness of specimens were measured by a high-speed video camera. The stress and strain histories of specimens, the thickness and the diameter in the simulations at high strain rate were compared with those in the experiments
  •  
43.
  • Oberstedt, S., et al. (author)
  • Correlation measurements of fission-fragment properties
  • 2010
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X.
  • Conference paper (peer-reviewed)abstract
    • For the development of future nuclear fission applications and for a responsible handling of nuclear waste the a-priori assessment of the fission-fragments' heat production and toxicity is a fundamental necessity. The success of an indispensable modelling of the fission process strongly depends on a good understanding of the particular mechanism of scission, the mass fragmentation and partition of excitation energy. Experimental observables are fission-fragment properties like mass- and energy-distributions, and the prompt neutron as well as γ-ray multiplicities and emission spectra. The latter quantities should preferably be known as a function of fragment mass and excitation energy. Those data are highly demanded as published by the OECD-NEA in its high priority data request list. With the construction of the double (v, E) spectrometer VERDI we aim at measuring pre- and post-neutron masses directly and simultaneously to avoid prompt neutron corrections. From the simultaneous measurement of pre- and post-neutron fission-fragment data the prompt neutron multiplicity may then be inferred fully correlated with fragment mass yield and total kinetic energy. Using an ultra-fast fission event trigger spectral prompt fission γ-ray measurements may be performed. For that purpose recently developed lanthanum-halide detectors, with excellent timing characteristics, were coupled to the VERDI spectrometer allowing for a very good discrimination of fission γ-rays and prompt neutrons due to their different time-of-flight.
  •  
44.
  • Pietralla, N., et al. (author)
  • On the Road to FAIR: 1st Operation of AGATA in PreSPEC at GSI
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X. - 9782759811755 - 9782759811762 ; 66, s. 02083-02083
  • Conference paper (peer-reviewed)abstract
    • The Facility for Antiproton and Ion Research (FAIR), under construction at Darmstadt will provide intense relativistic beams of exotic nuclei at its Superconducting-FRagment Separator. High-resolution in-beam γ-ray spectroscopy will be performed in the HISPEC experiment, using the European Advanced GAmma-ray Tracking Array (AGATA). The PreSPEC-AGATA campaign is the predecessor of HISPEC and runs from 2012 to 2014 at GSI Helmholtzzentrum für Schwerionenforschung GmbH. Up to19 AGATA modules were used at GSI's F Ragment Separator in 2012. We report on the status of the experiment including preliminary results from performance commissioning.
  •  
45.
  • Pomp, Stephan, et al. (author)
  • A Medley with over ten years of (mostly) light-ion production measurements at The Svedberg Laboratory
  • 2010
  • In: EFNUDAT. - : EDP Sciences. - 9782759805853 ; , s. 07013-
  • Conference paper (other academic/artistic)abstract
    • Over the past years an experimental programme has been run at the neutron beam of The Svedberg Laboratory with the aim to study light-ion production induced by 96 and 175 MeV neutrons for a wide variety of targets. The measurements have been conducted using the Medley facility which allows measurement of p, d, t, He-3 and alpha production at fixed angles (from 20 to 160 degrees in steps of 20 degrees) over a wide dynamic range. An overview of the results obtained at the now finished campaign at 96 MeV will be given. Since 2007 we have been running at 175 MeV with C, O, Si, Fe, Bi and U as target material. Preliminary results from these measurements will be shown and compared to model calculations with Talys-1.2. We also summarize the Medley measurements of elastic np and nd scattering and of angular distributions of fission fragments.
  •  
46.
  • Ricciarini, S. B., et al. (author)
  • PAMELA mission : Heralding a new era in cosmic ray physics
  • 2014
  • In: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X.
  • Conference paper (peer-reviewed)abstract
    • After seven years of data taking in space, the experiment PAMELA is showing very interesting features in cosmic rays, namely in the fluxes of protons, helium, electrons, that might change our basic vision of the mechanisms of production, acceleration and propagation of cosmic rays in the galaxy. In addition, PAMELA measurements of cosmic antiproton and positron fluxes are setting strong constraints to the nature of Dark Matter. The continuous particle detection is allowing a constant monitoring of the solar activity and detailed study of the solar modulation for a long period, giving important improvements to the comprehension of the heliosphere mechanisms. PAMELA is also measuring the radiation environment around the Earth, and has recently discovered an antiproton radiation belt.
  •  
47.
  • Slemr, F., et al. (author)
  • CARIBIC observations of gaseous mercury in the upper troposphere and lower stratosphere
  • 2013
  • In: Proceedings of the 16th International Conference on Heavy Metals in the Environment. - : EDP Sciences. - 2100-014X. ; 1
  • Conference paper (peer-reviewed)abstract
    • A unique set of gaseous mercury measurements in the upper troposphere and lower stratosphere (UT/LS) has been obtained during the monthly CARIBIC (www.caribic-atmospheric.com) flights since May 2005. The passenger Airbus 340-600 of Lufthansa covered routes to the Far East, North America, India, and the southern hemisphere. The accompanying measurements of CO, O3, NOy, H2O, aerosols, halocarbons, hydrocarbons, greenhouse gases, and several other parameters as well as backward trajectories enable a detailed analysis of these measurements. Speciation tests have shown that the CARIBIC measurements represent a good approximation of total gaseous mercury (TGM) concentrations. Above the tropopause TGM always decrease with increasing potential vorticity (PV) and O3 which implies its conversion to particle bound mercury. The observation of the lowest TGM concentrations at the highest particle concentrations in the stratosphere provides further evidence for such conversion. We will show how a seasonally dependent conversion rate could be derived using concomitantly measured SF6 mixing ratios as a timer. Tropospheric mercury data suggest the existence of a decreasing trend in the northern hemisphere whose size is comparable with the trend derived from long-term measurements by ship cruises, at Cape Point (South Africa) and Mace Head (Ireland).
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