Author
V. M. Gehman
Other affiliations: Virginia Tech, Los Alamos National Laboratory
Bio: V. M. Gehman is an academic researcher from Lawrence Berkeley National Laboratory. The author has contributed to research in topics: Double beta decay & Xenon. The author has an hindex of 38, co-authored 112 publications receiving 8810 citations. Previous affiliations of V. M. Gehman include Virginia Tech & Los Alamos National Laboratory.
Topics: Double beta decay, Xenon, MAJORANA, Neutrino, Time projection chamber
Papers published on a yearly basis
Papers
More filters
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
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
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
11 Mar 2009-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: Borexino as discussed by the authors, a large volume detector for low energy neutrino spectroscopy, is currently running underground at the Laboratori Nazionali del Gran Sasso, Italy.
Abstract: Borexino, a large volume detector for low energy neutrino spectroscopy, is currently running underground at the Laboratori Nazionali del Gran Sasso, Italy. The main goal of the experiment is the real-time measurement of sub-MeV solar neutrinos, and particularly of the monoenergetic (862 keV) 7 Be electron capture neutrinos, via neutrino–electron scattering in an ultra-pure liquid scintillator. This paper is mostly devoted to the description of the detector structure, the photomultipliers, the electronics, and the trigger and calibration systems. The real performance of the detector, which always meets, and sometimes exceeds, design expectations, is also shown. Some important aspects of the Borexino project, i.e. the fluid handling plants, the purification techniques and the filling procedures, are not covered in this paper and are, or will be, published elsewhere (see Introduction and Bibliography).
364 citations
Journal Article•
TL;DR: The Long-Baseline Neutrino Experiment (LBNE) as mentioned in this paper is an extensively developed plan for a world-class experiment dedicated to addressing the early evolution of our universe, its current state and its eventual fate.
Abstract: The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.
328 citations
Cited by
More filters
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
TL;DR: In this article, the authors present a review of the application of atomic physics to address important challenges in physics and to look for variations in the fundamental constants, search for interactions beyond the standard model of particle physics and test the principles of general relativity.
Abstract: Advances in atomic physics, such as cooling and trapping of atoms and molecules and developments in frequency metrology, have added orders of magnitude to the precision of atom-based clocks and sensors. Applications extend beyond atomic physics and this article reviews using these new techniques to address important challenges in physics and to look for variations in the fundamental constants, search for interactions beyond the standard model of particle physics, and test the principles of general relativity.
1,077 citations
Columbia University1, University of Amsterdam2, University of Mainz3, University of Coimbra4, New York University Abu Dhabi5, University of Zurich6, Stockholm University7, Rensselaer Polytechnic Institute8, Max Planck Society9, Weizmann Institute of Science10, University of Freiburg11, Purdue University12, University of Nantes13, University of Bologna14, University of California, San Diego15, University of Münster16, University of Chicago17, Rice University18, Pierre-and-Marie-Curie University19, University of California, Los Angeles20
TL;DR: The first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in Italy, are reported and a profile likelihood analysis shows that the data are consistent with the background-only hypothesis.
Abstract: We report the first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in Italy and the first ton-scale detector of this kind The blinded search used 342 live days of data acquired between November 2016 and January 2017 Inside the (1042±12)-kg fiducial mass and in the [5,40] keVnr energy range of interest for weakly interacting massive particle (WIMP) dark matter searches, the electronic recoil background was (193±025)×10-4 events/(kg×day×keVee), the lowest ever achieved in such a dark matter detector A profile likelihood analysis shows that the data are consistent with the background-only hypothesis We derive the most stringent exclusion limits on the spin-independent WIMP-nucleon interaction cross section for WIMP masses above 10 GeV/c2, with a minimum of 77×10-47 cm2 for 35-GeV/c2 WIMPs at 90% CL
1,061 citations
TL;DR: The theoretical and experimental issues relevant to neutrinoless double beta decay are reviewed in this paper, with significant emphasis on proposals favored by recent panel reviews, and the importance of and challenges in the calculation of nuclear matrix elements that govern the decay are considered in detail.
Abstract: The theoretical and experimental issues relevant to neutrinoless double beta decay are reviewed. The impact that a direct observation of this exotic process would have on elementary particle physics, nuclear physics, astrophysics, and cosmology is profound. Now that neutrinos are known to have mass and experiments are becoming more sensitive, even the nonobservation of neutrinoless double beta decay will be useful. If the process is actually observed, we will immediately learn much about the neutrino. The status and discovery potential of proposed experiments are reviewed in this context, with significant emphasis on proposals favored by recent panel reviews. The importance of and challenges in the calculation of nuclear matrix elements that govern the decay are considered in detail. The increasing sensitivity of experiments and improvements in nuclear theory make the future exciting for this field at the interface of nuclear and particle physics.
887 citations
Perimeter Institute for Theoretical Physics1, Niigata University2, CERN3, University of Connecticut4, Leiden University5, Korea Astronomy and Space Science Institute6, Federico Santa María Technical University7, University of California, Santa Barbara8, University of Maryland, College Park9, University of Lyon10, Claude Bernard University Lyon 111, Northwestern University12, University of Victoria13, University of Manchester14, University of Bonn15, Technische Universität München16, École Polytechnique Fédérale de Lausanne17, Stony Brook University18, Autonomous University of Madrid19, Centre national de la recherche scientifique20, University of Paris21, Moscow Institute of Physics and Technology22, Autonomous University of Barcelona23, University of Copenhagen24, Université libre de Bruxelles25, University of La Serena26, University of Valencia27, Taras Shevchenko National University of Kyiv28, Heidelberg University29, Yonsei University30, Princeton University31, Harvard University32, University of Geneva33, Tomsk State University34, University of Tübingen35, Tomsk Polytechnic University36, University of Washington37, University of Florida38, University of Hamburg39, TRIUMF40, University of Iowa41, University of Grenoble42, International Centre for Theoretical Physics43, Hokkai Gakuen University44, University of Illinois at Urbana–Champaign45, Durham University46, University of Melbourne47, University of Naples Federico II48, York University49, Lawrence Berkeley National Laboratory50, University of California, Berkeley51
TL;DR: It is demonstrated that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.
Abstract: This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (search for hidden particles) experiment is intended to hunt for new physics in the largely unexplored domain of very weakly interacting particles with masses below the Fermi scale, inaccessible to the LHC experiments, and to study tau neutrino physics. The same proton beam setup can be used later to look for decays of tau-leptons with lepton flavour number non-conservation, $\tau \to 3\mu $ and to search for weakly-interacting sub-GeV dark matter candidates. We discuss the evidence for physics beyond the standard model and describe interactions between new particles and four different portals—scalars, vectors, fermions or axion-like particles. We discuss motivations for different models, manifesting themselves via these interactions, and how they can be probed with the SHiP experiment and present several case studies. The prospects to search for relatively light SUSY and composite particles at SHiP are also discussed. We demonstrate that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.
842 citations