L. W. Koerner
A5086838396- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Nuclear Physics and Applications
- Pulsars and Gravitational Waves Research
- Planetary Science and Exploration
- Nuclear reactor physics and engineering
- Particle accelerators and beam dynamics
- Radiation Therapy and Dosimetry
- Methane Hydrates and Related Phenomena
- Muon and positron interactions and applications
- Atmospheric Ozone and Climate
- Noncommutative and Quantum Gravity Theories
- Quantum, superfluid, helium dynamics
- Scientific Research and Discoveries
- Advanced NMR Techniques and Applications
University of Houston
2018-2024
China Institute of Atomic Energy
2019
Shandong University
2019
The NOvA experiment has made a $4.4\sigma$-significant observation of $\bar\nu_{e}$ appearance in 2 GeV $\bar\nu_{\mu}$ beam at distance 810 km. Using $12.33\times10^{20}$ protons on target delivered to the Fermilab NuMI neutrino beamline, recorded 27 $\bar\nu_{\mu} \rightarrow \bar\nu_{e}$ candidates with background 10.3 and 102 \bar\nu_{\mu}$ candidates. This new antineutrino data is combined measure oscillation parameters $|\Delta m^2_{32}| = 2.48^{+0.11}_{-0.06}\times10^{-3}$ eV$^2/c^4$,...
We present updated results from the NOvA experiment for $\nu_\mu\rightarrow\nu_\mu$ and $\nu_\mu\rightarrow\nu_e$ oscillations an exposure of $8.85\times10^{20}$ protons on target, which represents increase 46% compared to our previous publication. The utilize significant improvements in both simulations analysis data. A joint fit data $\nu_\mu$ disappearance $\nu_e$ appearance gives best point as normal mass hierarchy, $\Delta m^2_{32} = 2.44\times 10^{-3}{{\rm eV}^2}/c^4$,...
A search for mixing between active neutrinos and light sterile has been performed by looking muon neutrino disappearance in two detectors at baselines of 1.04 735 km, using a combined MINOS MINOS+ exposure 16.36×10^{20} protons on target. simultaneous fit to the charged-current neutral-current energy spectra yields no evidence 3+1 model. The most stringent limit date is set parameter sin^{2}θ_{24} values mass splitting Δm_{41}^{2}>10^{-4} eV^{2}.
The violation of Baryon Number, $\mathcal{B}$, is an essential ingredient for the preferential creation matter over antimatter needed to account observed baryon asymmetry in universe. However, such a process has yet be experimentally observed. HIBEAM/NNBAR %experiment program proposed two-stage experiment at European Spallation Source (ESS) search number violation. will include high-sensitivity searches processes that violate by one or two units: free neutron-antineutron oscillation...
Searches for electron antineutrino, muon neutrino, and antineutrino disappearance driven by sterile neutrino mixing have been carried out the Daya Bay MINOS+ collaborations. This Letter presents combined results of these searches, along with exclusion from Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on θ_{μe} angle are derived that constitute most constraining limits to date over five orders magnitude mass-squared...
We report the final measurement of neutrino oscillation parameters $\mathrm{\ensuremath{\Delta}}{m}_{32}^{2}$ and ${\mathrm{sin}}^{2}{\ensuremath{\theta}}_{23}$ using all data from MINOS $\mathrm{MINOS}+$ experiments. These were collected a total exposure $23.76\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons on target producing ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$ beams 60.75 kt yr to atmospheric neutrinos. The disappearance...
Abstract The two-detector design of the NOvA neutrino oscillation experiment, in which two functionally identical detectors are exposed to an intense beam, aids canceling leading order effects cross-section uncertainties. However, limited knowledge interaction cross sections still gives rise some largest systematic uncertainties current measurements. We show contemporary models interactions be discrepant with data from NOvA, consistent discrepancies seen other experiments. Adjustments GENIE...
Abstract Baryon number conservation is not guaranteed by any fundamental symmetry within the standard model, and therefore has been a subject of experimental theoretical scrutiny for decades. So far, no evidence baryon violation observed. Large underground detectors have long used both neutrino detection searches violating processes. The next generation large will seek to improve upon limits set past current experiments cover range lifetimes predicted several Grand Unified Theories. In this...
Abstract Measuring observables to constrain models using maximum-likelihood estimation is fundamental many physics experiments. Wilks' theorem provides a simple way construct confidence intervals on model parameters, but it only applies under certain conditions. These conditions, such as nested hypotheses and unbounded are often violated in neutrino oscillation measurements other experimental scenarios. Monte Carlo methods can address these issues, albeit at increased computational cost. In...
A search for a time-varying ${\overline{\ensuremath{\nu}}}_{e}$ signal was performed with 621 days of data acquired by the Daya Bay Reactor Neutrino Experiment over 704 calendar days. The time spectrum measured flux normalized to its prediction analyzed Lomb-Scargle periodogram, which yielded no significant periods ranging from 2 hours nearly years. also fit sidereal modulation under Standard Model Extension (SME) framework Lorentz and $CPT$ violation (LV-CPTV). Limits were obtained all six...
The NOvA long-baseline neutrino experiment uses a pair of large, segmented, liquid-scintillator calorimeters to study oscillations, using GeV-scale neutrinos from the Fermilab NuMI beam. These detectors are also sensitive flux which emitted during core-collapse supernova through inverse beta decay interactions on carbon at energies $\mathcal{O}(10~\text{MeV})$. This signature provides means dominant mode energy release for occurring in our galaxy. We describe data-driven software trigger...
We report cross-section measurements of the final-state muon kinematics for ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ charged-current interactions in NOvA near detector using an accumulated $8.09\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons on target NuMI beam. present results as a double-differential cross section observed outgoing energy and angle, well single-differential sections derived neutrino energy, ${E}_{\ensuremath{\nu}}$, square four-momentum transfer, ${Q}^{2}$. compare to...
The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using $8.02\times10^{20}$ protons-on-target (POT) NuMI beam. sample of GeV interactions largest analyzed to date and limited by $\simeq$ 17\% systematic rather than 7.4\% statistical uncertainties. double-differential final-state energy angle presented for first time, together with single-differential dependence on $Q^{2}$ (squared four-momentum transfer) energy, range 1 $ \leq E_{\nu} < $6...
We report the first measurement of neutron cross section on argon in energy range 100-800 MeV. The was obtained with a 4.3-h exposure Mini-CAPTAIN detector to WNR/LANSCE beam at LANL. total is measured from attenuation coefficient flux as it traverses liquid volume. A set 2631 candidate interactions divided bins kinetic calculated time-of-flight measurements. These are reconstructed custom-made algorithms specifically designed for data time projection chamber size detector. averaged...
Neutrons produced by cosmic ray muons are an important background for underground experiments studying neutrino oscillations, neutrinoless double beta decay, dark matter, and other rare-event signals. A measurement of the neutron yield in three different experimental halls Daya Bay Reactor Neutrino Experiment at varying depth is reported. The Bay's liquid scintillator measured to be $Y_n=(10.26\pm 0.86)\times 10^{-5}$, $(10.22\pm 0.87)\times $(17.03\pm 1.22)\times...
The cross section of neutrino-induced neutral-current coherent ${\ensuremath{\pi}}^{0}$ production on a carbon-dominated target is measured in the NOvA near detector. This measurement uses narrow-band neutrino beam with an average energy 2.7 GeV, which interest to ongoing and future long-baseline oscillation experiments. measured, flux-averaged...
Using two years of data from the NOvA Near Detector at Fermilab, we report a seasonal variation cosmic ray induced multiple-muon event rates which has an opposite phase to in atmospheric temperature. The strength multipl$ increase as function muon multiplicity. However, no significant dependence is seen zenith angle, or spatial angular separation between correlated muons.
This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions two NOvA detectors, at distances 1 and 810 km beam source, is analyzed using exposure 12.51×10^{20} protons-on-target NuMI Fermilab running antineutrino mode. A total 121 candidates are observed far detector, compared to a prediction 122±11(stat.)±15(syst.) assuming only between three active flavors. No...
Using the NOvA neutrino detectors, a broad search has been performed for any signal coincident with 28 gravitational wave events detected by LIGO/Virgo Collaboration between September 2015 and July 2019. For all of these events, is sensitive to possible arrival neutrinos cosmic rays GeV higher energies. five (seven) in Far (Near) Detector, timely public alerts from allowed recording MeV-scale events. No candidates were found.
We report an extended measurement of the neutron cross section on argon in energy range 95--720 MeV. The was obtained with a 4.3-hour exposure Mini-CAPTAIN detector to WNR/LANSCE beam at LANL. Compared earlier analysis same data, this includes reassessment systematic uncertainties, particular related unused wires upstream part detector. Using information we doubled fiducial volume experiment and increased statistics by factor 2.4. also shifted from bins time-of-flight bins. This change...
Cross sections for the interaction $\nu_\mu A\rightarrow\mu^-\pi^0 X$ with neutrino energies between 1 and 5~GeV are measured using a sample of 165k selected events collected in NOvA experiment's Near Detector, hydrocarbon-based detector exposed to NuMI beam at Fermi National Accelerator Laboratory. Results presented as flux-averaged total cross section differential momenta angles outgoing muon $\pi^0$, four-momentum transfer, invariant mass hadronic system. Comparisons made predictions from...
We report the rate of cosmic ray air showers with multiplicities exceeding 15 muon tracks recorded in NOvA Far Detector between May 2016 and 2018. The detector is located on surface under an overburden 3.6 meters water equivalent. observe a seasonal dependence multiple-muon showers, which varies magnitude multiplicity zenith angle. During this period, effective atmospheric temperature pressure ranged 210 K 230 940 mbar 990 mbar, respectively; shower rates are anticorrelated variation...
A high precision calibration of the nonlinearity in energy response Daya Bay Reactor Neutrino Experiment's antineutrino detectors is presented detail. The originates from particle-dependent light yield scintillator and charge-dependent electronics response. model constrained by $\gamma$ points deployed naturally occurring radioactive sources, $\beta$ spectrum $^{12}$B decays, a direct measurement with new flash analog-to-digital converter readout system. Less than 0.5% uncertainty achieved...