J. E. Y. Dobson
A5042429963- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Atomic and Subatomic Physics Research
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Cosmology and Gravitation Theories
- Scientific Research and Discoveries
- Quantum Chromodynamics and Particle Interactions
- Radiation Detection and Scintillator Technologies
- Computational Physics and Python Applications
- Nuclear Physics and Applications
- Quantum, superfluid, helium dynamics
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Radiation Therapy and Dosimetry
- Simulation Techniques and Applications
- Particle accelerators and beam dynamics
- Astronomy and Astrophysical Research
- Context-Aware Activity Recognition Systems
- Nuclear and radioactivity studies
- Geophysics and Gravity Measurements
- Nuclear reactor physics and engineering
- Pneumonia and Respiratory Infections
- Health, Environment, Cognitive Aging
The King's College
2023-2024
King's College Hospital
2023-2024
King's College London
2023-2024
University College London
2016-2023
Imperial College London
2009-2016
University of Edinburgh
2014-2016
École Polytechnique
2011
Laboratoire Leprince-Ringuet
2011
Centre National de la Recherche Scientifique
2011
We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35×104 kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 active mass is operated at Sanford 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 nuclear recoils. At 50 GeV c−2,...
The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Research Facility (Lead, South Dakota). LUX cryostat was filled for first time in underground laboratory February 2013. We report results of WIMP search data set, taken during period from April to August 2013, presenting analysis 85.3 live days with fiducial volume 118 kg. A profile-likelihood technique shows our be consistent background-only hypothesis, allowing 90% confidence...
The T2K experiment observes indications of ν(μ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario |Δm(23)(2)| = 2.4×10(-3) eV(2), sin(2)2θ(23) 1 and sin(2)2θ(13) 0, expected number such is 1.5±0.3(syst). Under this hypothesis, probability to observe six or more candidate 7×10(-3), equivalent 2.5σ significance. At 90% C.L., are consistent 0.03(0.04) < 0.28(0.34)...
The LUX-ZEPLIN experiment is a dark matter detector centered on dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60~live days using fiducial mass 5.5 t. A profile-likelihood ratio analysis shows data to be consistent background-only hypothesis, setting new limits spin-independent...
We present constraints on weakly interacting massive particles (WIMP)-nucleus scattering from the 2013 data of Large Underground Xenon dark matter experiment, including 1.4×104 kg day search exposure. This new analysis incorporates several advances: single-photon calibration at scintillation wavelength, improved event-reconstruction algorithms, a revised background model events originating detector walls in an enlarged fiducial volume, and calibrations decays injected tritium β source...
LUX-ZEPLIN (LZ) is a next-generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using two-phase xenon detector with an active mass of 7 tonnes, LZ search primarily for low-energy interactions weakly interacting massive particles (WIMPs), which are hypothesized to make up our galactic halo. In this paper, projected WIMP sensitivity presented based on latest background estimates...
We present experimental constraints on the spin-dependent WIMP-nucleon elastic cross sections from total 129.5 kg-year exposure acquired by Large Underground Xenon experiment (LUX), operating at Sanford Research Facility in Lead, South Dakota (USA). A profile likelihood ratio analysis allows 90% CL upper limits to be set WIMP-neutron (WIMP-proton) section of $\sigma_n$ = 1.6$\times 10^{-41}$ cm$^{2}$ ($\sigma_p$ 5$\times 10^{-40}$ cm$^{2}$) 35 GeV$c^{-2}$, almost a sixfold improvement over...
The Tokai-to-Kamioka (T2K) experiment studies neutrino oscillations using an off-axis muon beam with a peak energy of about 0.6 GeV that originates at the J-PARC accelerator facility. Interactions neutrinos are observed near detectors placed 280 m from production target and far detector -- Super-Kamiokande (SK) located 295 km away. flux prediction is essential part successful interaction rates T2K important input to oscillation cross section measurements. A FLUKA GEANT3 based simulation...
The field of dark matter detection is a highly visible and competitive one. In this paper, we propose recommendations for presenting direct results particularly suited weak-scale searches, although believe the spirit can apply more broadly to searches other candidates, such as very light or axions. To translate experimental data into final published result, collaborations must make series choices in their analysis, ranging from how model astrophysical parameters statistical inferences based...
The T2K collaboration: reports evidence for electron neutrino appearance at the atmospheric mass splitting, |\Delta m_{32}^2|=2.4x10^{-3} eV^2. An excess of interactions over background is observed from a muon beam with peak energy 0.6 GeV Super-Kamiokande (SK) detector 295 km beam's origin. Signal and predictions are constrained by data near detectors located 280 m production target. We observe 11 candidate events SK when 3.3\pm0.4(syst.) expected. background-only hypothesis rejected...
We present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. is a dual-phase xenon time projection chamber operating at Sanford Underground Research Facility (Lead, South Dakota), which designed to observe recoil signature of galactic WIMPs scattering nuclei. A profile likelihood ratio analysis 1.4×104 kg day fiducial exposure allows 90% C.L. upper limits be set WIMP-neutron (WIMP-proton)...
The design and performance of the LUX-ZEPLIN (LZ) detector is described as March 2015 in this Conceptual Design Report. LZ a second-generation dark-matter with potential for unprecedented sensitivity to weakly interacting massive particles (WIMPs) masses from few GeV/c2 hundreds TeV/c2. With total liquid xenon mass about 10 tonnes, will be most sensitive experiment WIMPs region by end decade. This report describes detail technical systems. Expected backgrounds are quantified presented....
The first searches for axions and axionlike particles with the Large Underground Xenon experiment are presented. Under assumption of an axioelectric interaction in xenon, coupling constant between electrons ${g}_{\mathrm{Ae}}$ is tested using data collected 2013 exposure totaling 95 live days $\ifmmode\times\else\texttimes\fi{}118\text{ }\text{ }\mathrm{kg}$. A double-sided, profile likelihood ratio statistic test excludes larger than...
T2K has performed the first measurement of ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ inclusive charged current interactions on carbon at neutrino energies $\ensuremath{\sim}1\text{ }\text{ }\mathrm{GeV}$ where is reported as a flux-averaged double differential cross section in muon momentum and angle. The flux predicted by beam Monte Carlo external data, including results from NA61/SHINE experiment. data used for this were taken 2010 2011, with total...
We present measurements of the electron-recoil (ER) response LUX dark matter detector based upon 170 000 highly pure and spatially uniform tritium decays. reconstruct energy spectrum using combined model find good agreement with expectations. report average charge light yields ER events in liquid xenon at 180 $105\text{ }\text{ }\mathrm{V}/\mathrm{cm}$ compare results to NEST model. also measure mean recombination fraction its fluctuations, we investigate location width band. These provide...
Following the first science results of LUX-ZEPLIN (LZ) experiment, a dual-phase xenon time projection chamber operating from Sanford Underground Research Facility in Lead, South Dakota, USA, we report initial limits on model-independent nonrelativistic effective field theory describing complete set possible interactions weakly interacting massive particle (WIMP) with nucleon. These utilize same 5.5 t fiducial mass and 60 live days exposure collected for LZ spin-independent spin-dependent...
We report a measurement of muon-neutrino disappearance in the T2K experiment. The 295-km beam from Tokai to Kamioka is first implementation off-axis technique long-baseline neutrino oscillation With data corresponding $1.43\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons on target, we observe 31 fully-contained single $\ensuremath{\mu}$-like ring events Super-Kamiokande, compared with an expectation $104\ifmmode\pm\else\textpm\fi{}14\text{ }(\mathrm{syst})$ without oscillations. best-fit...
Abstract LUX-ZEPLIN (LZ) is a second-generation direct dark matter experiment with spin-independent WIMP-nucleon scattering sensitivity above $${1.4 \times 10^{-48}}\, {\hbox {cm}}^{2}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>1.4</mml:mn> <mml:mo>×</mml:mo> <mml:msup> <mml:mn>10</mml:mn> <mml:mo>-</mml:mo> <mml:mn>48</mml:mn> </mml:mrow> </mml:msup> <mml:mspace/> <mml:mtext>cm</mml:mtext> <mml:mn>2</mml:mn> </mml:math> for WIMP mass of $${40}\, \hbox...
The LUX-ZEPLIN experiment recently reported limits on WIMP-nucleus interactions from its initial science run, down to $6.5\times10^{-48}$ cm$^2$ for the spin-independent interaction of a 30 GeV/c$^2$ WIMP at 90% confidence level. In this paper, we present comprehensive analysis backgrounds important result and other upcoming physics analyses, including neutrinoless double-beta decay searches effective field theory interpretations data. We confirm that in-situ determinations bulk fixed...
The LUX-ZEPLIN (LZ) experiment is a dark matter detector centered on dual-phase xenon time projection chamber. We report searches for new physics appearing through few-keV-scale electron recoils, using the experiment's first exposure of 60 live days and fiducial mass 5.5 t. data are found to be consistent with background-only hypothesis, limits set models including solar axion coupling, neutrino magnetic moment millicharge, couplings galactic axionlike particles hidden photons. Similar...
Searches for dark matter with liquid xenon time projection chamber experiments have traditionally focused on the region of parameter space that is characteristic weakly interacting massive particles, ranging from a few GeV/$c^2$ to TeV/$c^2$. Models mass much heavier than this are well motivated by early production mechanisms different standard thermal freeze-out, but they generally been less explored experimentally. In work, we present re-analysis first science run (SR1) LZ experiment, an...