A5062493765- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Nuclear Physics and Applications
- Radiation Detection and Scintillator Technologies
- Nuclear reactor physics and engineering
- Atomic and Subatomic Physics Research
- Muon and positron interactions and applications
- Semiconductor Lasers and Optical Devices
- Geophysics and Gravity Measurements
- Nuclear physics research studies
- Noncommutative and Quantum Gravity Theories
- Quantum, superfluid, helium dynamics
- Nuclear Engineering Thermal-Hydraulics
- Field-Flow Fractionation Techniques
- Radiation Therapy and Dosimetry
- Particle accelerators and beam dynamics
- Atmospheric Ozone and Climate
- Particle Accelerators and Free-Electron Lasers
- Computational Physics and Python Applications
- Solar and Space Plasma Dynamics
- Quantum Mechanics and Applications
- Medical Imaging Techniques and Applications
Lawrence Livermore National Laboratory
2011-2016
University of Alabama
2005-2015
Kavli Institute for the Physics and Mathematics of the Universe
2014
The University of Tokyo
2014
Tohoku University
2014
Kansas State University
2008
The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio events 0.944±0.016(stat)±0.040(syst) was obtained in 101 days running at the nuclear power plant France, two 4.25 GW(th) reactors. results were from a single 10 m(3) fiducial volume detector located 1050 m cores. flux prediction used Bugey4 measurement after correction for differences core composition. deficit can be...
We present results of a study neutrino oscillation based on 766 ton-year exposure KamLAND to reactor anti-neutrinos. observe 258 \nuebar\ candidate events with energies above 3.4 MeV compared 365.2 expected in the absence oscillation. Accounting for 17.8 background events, statistical significance \nuebar disappearance is 99.998%. The observed energy spectrum disagrees spectral shape at 99.6% and prefers distortion from effects. A two-neutrino analysis data gives \DeltaMSq =...
The KamLAND experiment has determined a precise value for the neutrino oscillation parameter Deltam21(2) and stringent constraints on theta12. exposure to nuclear reactor antineutrinos is increased almost fourfold over previous results 2.44 x 10(32) proton yr due longer livetime an enlarged fiducial volume. An undistorted nu[over]e energy spectrum now rejected at >5sigma. Analysis of above inverse beta decay threshold, including geoneutrinos, gives best fit...
This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and latest astrophysical data.
The Double Chooz experiment has observed 8249 candidate electron antineutrino events in 227.93 live days with 33.71 GW-ton-years ($\mathrm{\text{reactor power}}\ifmmode\times\else\texttimes\fi{}\mathrm{\text{detector mass}}\ifmmode\times\else\texttimes\fi{}\mathrm{\text{live time}}$) exposure using a $10.3\text{ }\text{ }{\mathrm{m}}^{3}$ fiducial volume detector located at 1050 m from the reactor cores of nuclear power plant France. expectation case ${\ensuremath{\theta}}_{13}=0$ is 8937...
We present new constraints on the neutrino oscillation parameters $/textyen Delta m^{2}_{21}$, theta_{12}$, and theta_{13}$ from a three-flavor analysis of solar KamLAND data. The data set includes acquired following radiopurity upgrade amounts to total exposure $3.49 \textyen times 10^{32}$ target-proton-year. Under assumption {\textyen it CPT} invariance, two-flavor (/textyen mbox{$\textyen theta_{13} = 0$}) yields best-fit values $\textyen tan^{2} theta_{12} 0.444^{+0.036}_{-0.030}$...
Radioactive isotopes produced through cosmic muon spallation are a background for rare-event detection in $\nu$ detectors, double-$\beta$-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important future experiments aiming to determine pep CNO solar neutrino fluxes, which dominated by production $^{11}$C. Data from Kamioka liquid-scintillator antineutrino detector (KamLAND) provides valuable information better understanding these...
The Double Chooz experiment has determined the value of neutrino oscillation parameter $\theta_{13}$ from an analysis inverse beta decay interactions with neutron capture on hydrogen. This uses a three times larger fiducial volume than standard assessment, which is restricted to region doped gadolinium (Gd), yielding exposure 113.1 GW-ton-years. data sample used in this distinct that Gd analysis, and systematic uncertainties are also largely independent, some exceptions, such as reactor flux...
We present the results of a search for extraterrestrial electron antineutrinos ('s) in energy range using KamLAND detector. In an exposure 4.53 kton-year, we identify 25 candidate events. All events can be attributed to background, most importantly neutral current atmospheric neutrino interactions, setting upper limit on probability 8B solar νe's converting into 's at 5.3 × 10−5 (90% CL), if assume undistorted shape. This corresponds flux 93 cm−2 s−1 or event rate 1.6 (kton − year)−1 above...
We report a measurement of the neutrino-electron elastic scattering rate from ${}^{8}$B solar neutrinos based on 123 kton-day exposure KamLAND. The background-subtracted electron recoil rate, above 5.5-MeV analysis threshold is 1.49 $\ifmmode\pm\else\textpm\fi{}$ 0.14(stat) 0.17(syst) events per kton-day. Interpreted as due to pure flavor flux with neutrino spectrum, this corresponds spectrum integrated 2.77 0.26(stat) 0.32(syst) $\ifmmode\times\else\texttimes\fi{}$10${}^{6}$...
We report a measurement of the neutrino-electron elastic scattering rate 862 keV 7Be solar neutrinos based on 165.4 kton-day exposure KamLAND. The observed is 582 +/- 90 (kton-day)^-1, which corresponds to neutrino flux (3.26 0.50) x 10^9 cm^-2s^-1, assuming pure electron flavor flux. Comparing this with standard model prediction and further three mixing, nu_e survival probability 0.66 0.14 determined from KamLAND data. Utilizing global oscillation analysis, we obtain total (5.82 0.98)...
We present a search for Lorentz violation with 8249 candidate electron antineutrino events taken by the Double Chooz experiment in 227.9 live days of running. This analysis, featuring sidereal time dependence events, is first test invariance using reactor-based source. No variation data and disappearance results are consistent independent oscillations. Under Standard-Model Extension, we set limits on 14 violating coefficients associated transitions between tau flavor, two competitive muon flavor.
The Kamioka Liquid scintillator Anti-Neutrino Detector is used in a search for single neutron or two-neutron intranuclear disappearance that would produce holes the s-shell energy level of 12C nuclei. Such could be created as result nucleon decay into invisible modes (inv), e.g., n→3ν nn→2ν. deexcitation corresponding daughter nucleus results sequence space and time-correlated events observable liquid detector. We report on new limits one- disappearance: τ(n→inv)>5.8×1029 years...
Double Chooz is unique among modern reactor-based neutrino experiments studying $\bar \nu_e$ disappearance in that data can be collected with all reactors off. In this paper, we present from 7.53 days of reactor-off running. Applying the same selection criteria as used reactor-on oscillation analysis, a measured background rate 1.0$\pm$0.4 events/day obtained. The model for accidentals, cosmogenic $\beta$-$n$-emitting isotopes, fast neutrons cosmic muons, and stopped-$\mu$ decays analysis...
We have successfully built and operated a source deployment system for the KamLAND detector. This was used to position radioactive sources throughout delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, compatibility, safety requirements. The calibration data obtained with this device were fully characterize detector energy reconstruction biases. As result, uncertainty in size of fiducial volume reduced by factor two. Prior system, largest systematic...
Rising interest in nuclear reactors as a source of antineutrinos for experiments motivates validated, fast, and accessible simulations to predict reactor fission rates. Here we present results from the DRAGON MURE simulation codes compare them other industry standards core modeling. We use published data Takahama-3 evaluate quality these against independently measured fuel isotopic composition. The propagation uncertainty operating parameters resulting antineutrino flux predictions is also discussed.