Author
F. Neves
Other affiliations: Imperial College London
Bio: F. Neves is an academic researcher from University of Coimbra. The author has contributed to research in topics: Neutron & Xenon. The author has an hindex of 40, co-authored 164 publications receiving 9303 citations. Previous affiliations of F. Neves include Imperial College London.
Topics: Neutron, Xenon, Dark matter, Scintillation, Neutron cross section
Papers published on a yearly basis
Papers
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Case Western Reserve University1, Imperial College London2, South Dakota School of Mines and Technology3, University of Maryland, College Park4, Yale University5, Lawrence Livermore National Laboratory6, University of South Dakota7, University of California, Santa Barbara8, Brown University9, University of Coimbra10, University of Edinburgh11, University of Rochester12, Lawrence Berkeley National Laboratory13, University of California, Davis14, University College London15, University of California, Berkeley16, Texas A&M University17, Harvard University18
TL;DR: The first WIMP search data set is reported, taken during the period from April to August 2013, presenting the analysis of 85.3 live days of data, finding that the LUX data are in disagreement with low-mass W IMP signal interpretations of the results from several recent direct detection experiments.
Abstract: The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota). The LUX cryostat was filled for the first time in the underground laboratory in February 2013. We report results of the first WIMP search data set, taken during the period from April to August 2013, presenting the analysis of 85.3 live days of data with a fiducial volume of 118 kg. A profile-likelihood analysis technique shows our data to be consistent with the background-only hypothesis, allowing 90% confidence limits to be set on spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6 × 10(-46) cm(2) at a WIMP mass of 33 GeV/c(2). We find that the LUX data are in disagreement with low-mass WIMP signal interpretations of the results from several recent direct detection experiments.
1,962 citations
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Case Western Reserve University1, University of Wisconsin-Madison2, Imperial College London3, South Dakota School of Mines and Technology4, University of Maryland, College Park5, University of California, Berkeley6, Lawrence Livermore National Laboratory7, University of Coimbra8, University of South Dakota9, Yale University10, University of California, Santa Barbara11, Brown University12, University of California, Davis13, Lawrence Berkeley National Laboratory14, University College London15, University of Rochester16, SLAC National Accelerator Laboratory17, Texas A&M University18, State University of New York System19, University of Edinburgh20
TL;DR: This search yields no evidence of WIMP nuclear recoils and constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35×10^{4} kg day exposure of the Large Underground Xenon experiment are reported.
Abstract: We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35×10^{4} kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50 GeV c^{-2}, WIMP-nucleon spin-independent cross sections above 2.2×10^{-46} cm^{2} are excluded at the 90% confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1×10^{-46} cm^{2} at 50 GeV c^{-2}.
1,844 citations
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Case Western Reserve University1, Imperial College London2, South Dakota School of Mines and Technology3, University of Maryland, College Park4, University of Edinburgh5, Yale University6, Lawrence Livermore National Laboratory7, University of California, Santa Barbara8, Brown University9, University of South Dakota10, University of California, Davis11, University of Coimbra12, Lawrence Berkeley National Laboratory13, University College London14, University of Rochester15, University of California, Berkeley16, SLAC National Accelerator Laboratory17, Texas A&M University18, State University of New York System19
TL;DR: This new analysis incorporates several advances: single-photon calibration at the scintillation wavelength, improved event-reconstruction algorithms, a revised background model including events originating on the detector walls in an enlarged fiducial volume, and new calibrations from decays of an injected tritium β source and from kinematically constrained nuclear recoils down to 1.1 keV.
Abstract: We present constraints on weakly interacting massive particles (WIMP)-nucleus scattering from the 2013 data of the Large Underground Xenon dark matter experiment, including 1.4×10^{4} kg day of search exposure. This new analysis incorporates several advances: single-photon calibration at the scintillation wavelength, improved event-reconstruction algorithms, a revised background model including events originating on the detector walls in an enlarged fiducial volume, and new calibrations from decays of an injected tritium β source and from kinematically constrained nuclear recoils down to 1.1 keV. Sensitivity, especially to low-mass WIMPs, is enhanced compared to our previous results which modeled the signal only above a 3 keV minimum energy. Under standard dark matter halo assumptions and in the mass range above 4 GeV c^{-2}, these new results give the most stringent direct limits on the spin-independent WIMP-nucleon cross section. The 90% C.L. upper limit has a minimum of 0.6 zb at 33 GeV c^{-2} WIMP mass.
460 citations
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Case Western Reserve University1, South Dakota School of Mines and Technology2, Yale University3, Lawrence Livermore National Laboratory4, National Research Nuclear University MEPhI5, University of South Dakota6, Texas A&M University7, Brown University8, University of California, Davis9, University of Coimbra10, University of Maryland, College Park11, University of Rochester12, Lawrence Berkeley National Laboratory13, University of California, Berkeley14, University of California, Santa Barbara15, Harvard University16
11 Mar 2013-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: The Large Underground Xenon (LUX) detector as mentioned in this paper is a dual-phase Xenon detector with a spin independent cross-section per nucleon of 2 × 10 − 46 cm 2, equivalent to ∼ 1 event / 100 kg / month in the inner 100-kg fiducial volume (FV) of the 370-kg detector.
Abstract: The Large Underground Xenon (LUX) collaboration has designed and constructed a dual-phase xenon detector, in order to conduct a search for Weakly Interacting Massive Particles (WIMPs), a leading dark matter candidate. The goal of the LUX detector is to clearly detect (or exclude) WIMPS with a spin independent cross-section per nucleon of 2 × 10 − 46 cm 2 , equivalent to ∼ 1 event / 100 kg / month in the inner 100-kg fiducial volume (FV) of the 370-kg detector. The overall background goals are set to have 1 background events characterized as possible WIMPs in the FV in 300 days of running. This paper describes the design and construction of the LUX detector.
339 citations
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TL;DR: In this paper, the authors present constraints on WIMP-nucleus scattering from the 2013 data of the Large Underground Xenon (LUX) dark matter experiment, including $1.4\times10^{4}\,\mathrm{kg\cdot days}$ of search exposure.
Abstract: We present constraints on WIMP-nucleus scattering from the 2013 data of the Large Underground Xenon (LUX) dark matter experiment, including $1.4\times10^{4}\,\mathrm{kg\cdot days}$ of search exposure. This new analysis incorporates several advances: single-photon calibration at the scintillation wavelength; improved event-reconstruction algorithms; a revised background model including events originating on the detector walls in an enlarged fiducial volume; and new calibrations from decays of an injected tritium $\beta$ source and from kinematically constrained nuclear recoils down to 1.1 keV. Sensitivity, especially to low-mass WIMPs, is enhanced compared to our previous results which modeled the signal only above a 3 keV minimum energy. Under standard dark matter halo assumptions and in the mass range above 4 $\mathrm{GeV}\,c^{-2}$, these new results give the most stringent direct limits on the spin-independent WIMP-nucleon cross section. The 90% CL upper limit has a minimum of 0.6 zb at 33 $\mathrm{GeV}\,c^{-2}$ WIMP mass.
309 citations
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TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.
Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …
33,785 citations
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TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These
9,929 citations
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Los Alamos National Laboratory1, National Nuclear Data Center2, Oak Ridge National Laboratory3, Argonne National Laboratory4, Lawrence Livermore National Laboratory5, National Institute of Standards and Technology6, Rensselaer Polytechnic Institute7, Idaho National Laboratory8, Westinghouse Electric9, Atomic Energy of Canada Limited10, Nuclear Research and Consultancy Group11
TL;DR: The ENDF/B-VII.0 as discussed by the authors file contains data primarily for reactions with incident neutrons, protons, and photons on almost 400 isotopes, based on experimental data and theory predictions.
1,913 citations
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Columbia University1, University of Amsterdam2, University of Bologna3, University of Mainz4, University of Münster5, University of Coimbra6, New York University Abu Dhabi7, University of Zurich8, Stockholm University9, Rensselaer Polytechnic Institute10, Max Planck Society11, Weizmann Institute of Science12, University of Freiburg13, University of Nantes14, University of California, San Diego15, University of Chicago16, Purdue University17, Rice University18, Pierre-and-Marie-Curie University19, University of California, Los Angeles20
TL;DR: In this article, a search for weakly interacting massive particles (WIMPs) using 278.8 days of data collected with the XENON1T experiment at LNGS is reported.
Abstract: We report on a search for weakly interacting massive particles (WIMPs) using 278.8 days of data collected with the XENON1T experiment at LNGS. XENON1T utilizes a liquid xenon time projection chamber with a fiducial mass of (1.30±0.01) ton, resulting in a 1.0 ton yr exposure. The energy region of interest, [1.4,10.6] keVee ([4.9,40.9] keVnr), exhibits an ultralow electron recoil background rate of [82-3+5(syst)±3(stat)] events/(ton yr keVee). No significant excess over background is found, and a profile likelihood analysis parametrized in spatial and energy dimensions excludes new parameter space for the WIMP-nucleon spin-independent elastic scatter cross section for WIMP masses above 6 GeV/c2, with a minimum of 4.1×10-47 cm2 at 30 GeV/c2 and a 90% confidence level.
1,808 citations
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TL;DR: Aerogels form a new class of solids showing sophisticated potentialities for a range of applications, and can develop very attractive physical and chemical properties not achievable by other means of low temperature soft chemical synthesis.
Abstract: In the present review, aerogels designate dried gels with a very high relative pore volume. These are versatile materials that are synthesized in a first step by low-temperature traditional sol-gel chemistry. However, while in the final step most wet gels are often dried by evaporation to produce so-called xerogels, aerogels are dried by other techniques, essentially supercritical drying. As a result, the dry samples keep the very unusual porous texture which they had in the wet stage. In general these dry solids have very low apparent densities, large specific surface areas, and in most cases they exhibit amorphous structures when examined by X-ray diffraction (XRD) methods. In addition, they are metastable from the point of view of their thermodynamic properties. Consequently, they often undertake a structural evolution by chemical transformation, when aged in a liquid medium and/or heat treated. As aerogels combine the properties of being highly divided solids with their metastable character, they can develop very attractive physical and chemical properties not achievable by other means of low temperature soft chemical synthesis. In other words, they form a new class of solids showing sophisticated potentialities for a range of applications. These applications as well as chemical and physical aspects of these materials were regularly detailed and discussed in a series of symposia on aerogels,1-5 the last of them being held in Albuquerque in 2000.6 Reviews were also regularly published, either on both xerogels and aerogels7 or more focused on the applications of aerogels.8-13 The particularly interesting properties of aerogels arise from the extraordinary flexibility of the solgel processing, coupled with original drying techniques. The wet chemistry is not basically different for making xerogels and aerogels. As this common basis has been extensively detailed in recent books,14 it does not need to be reviewed. Compared to traditional xerogels, the originality of aerogels comes from * To whom all correspondence should be addressed. † Institut de Recherches sur la Catalyse. ‡ Laboratoire d’Application de la Chimie à l’Environnement. 4243 Chem. Rev. 2002, 102, 4243−4265
1,773 citations