- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Particle accelerators and beam dynamics
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Nuclear physics research studies
- Radiation Detection and Scintillator Technologies
- Muon and positron interactions and applications
- Noncommutative and Quantum Gravity Theories
- Atomic and Subatomic Physics Research
- Nuclear Physics and Applications
- Radio Astronomy Observations and Technology
- Particle Accelerators and Free-Electron Lasers
- Scientific Research and Discoveries
- Advanced Numerical Analysis Techniques
- Superconducting Materials and Applications
- Radiation Therapy and Dosimetry
- Brake Systems and Friction Analysis
- Crystallography and Radiation Phenomena
- Atmospheric Ozone and Climate
- X-ray Diffraction in Crystallography
- Mechanical Engineering and Vibrations Research
University of Minnesota, Duluth
2015-2024
Universidad de Guanajuato
2020-2024
Minerva Foundation
2022-2023
Daresbury Laboratory
2020-2022
University of Minnesota
1998-2020
Fermi National Accelerator Laboratory
2004-2016
University of Minnesota System
2006-2015
Astronomy and Space
2006-2015
University of Washington
2003-2011
University of Maryland, College Park
2008
We report the results of a search for ${\ensuremath{\nu}}_{e}$ appearance in ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ beam MINOS long-baseline neutrino experiment. With an improved analysis and increased exposure $8.2\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons on NuMI target at Fermilab, we find that $2{sin}^{2}({\ensuremath{\theta}}_{23}){sin}^{2}(2{\ensuremath{\theta}}_{13})<0.12(0.20)$ 90% confidence level $\ensuremath{\delta}=0$ normal (inverted) mass hierarchy, with best-fit...
We present measurements of nu_mu disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment. One hundred and twelve beam-originated events are observed fiducial volume Super-Kamiokande with an expectation 158.1^{+9.2}_{-8.6} without oscillation. A distortion energy spectrum is also seen 58 single-ring muon-like reconstructed energies. The probability that observations explained by for no 0.0015% (4.3sigma). In a two flavor scenario, allowed Delta m^2 region at...
This Letter reports results from the MINOS experiment based on its initial exposure to neutrinos Fermilab NuMI beam. The rates and energy spectra of charged current ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ interactions are compared in two detectors located along beam axis at distances 1 735 km. With $1.27\ifmmode\times\else\texttimes\fi{}{10}^{20}$ 120 GeV protons incident target, 215 events with energies below 30 observed Far Detector, an expectation $336\ifmmode\pm\else\textpm\fi{}14$...
We present results for ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ oscillation in the KEK to Kamioka (K2K) long-baseline neutrino experiment. K2K uses an accelerator-produced beam with a mean energy of 1.3 GeV directed at Super-Kamiokande detector. observed energy-dependent disappearance ${\ensuremath{\nu}}_{\ensuremath{\mu}}$, which we presume have oscillated ${\ensuremath{\nu}}_{\ensuremath{\tau}}$. The probability that would observe these if there is no 0.0050% ($4.0\ensuremath{\sigma}$).
This Letter reports new results from the MINOS experiment based on a two-year exposure to muon neutrinos Fermilab NuMI beam. Our data are consistent with quantum-mechanical oscillations of neutrino flavor mass splitting |Deltam2| = (2.43+/-0.13) x 10(-3) eV2 (68% C.L.) and mixing angle sin2(2theta) > 0.90 (90% C.L.). disfavor two alternative explanations for disappearance in flight: namely, decays into lighter particles quantum decoherence neutrinos, at 3.7 5.7 standard-deviation levels,...
Measurements of neutrino oscillations using the disappearance muon neutrinos from Fermilab NuMI beam as observed by two MINOS detectors are reported. New analysis methods have been applied to an enlarged data sample exposure 7.25×10(20) protons on target. A fit yields values |Δm(2)|=(2.32(-0.08)(+0.12))×10(-3) eV(2) for atmospheric mass splitting and sin(2)(2θ)>0.90 (90% C.L.) mixing angle. Pure decay quantum decoherence hypotheses excluded at 7 9 standard deviations, respectively.
We report measurements of oscillation parameters from ν(μ) and disappearance using beam atmospheric data MINOS. The comprise exposures 10.71×10(20) protons on target in the ν(μ)-dominated beam, 3.36×10(20) ν(μ)-enhanced 37.88 kton yr neutrinos. Assuming identical ν parameters, we measure |Δm2| = (2.41(-0.10)(+0.09))×10(-3) eV2 sin2(2θ) 0.950(-0.036)(+0.035). Allowing independent oscillations, antineutrino (2.50(-0.25)(+0.23))×10(-3) 0.97(-0.08)(+0.03), with minimal change to neutrino parameters.
We report on a new analysis of neutrino oscillations in MINOS using the complete set accelerator and atmospheric data. The combines $\nu_{\mu}$ disappearance $\nu_{e}$ appearance data three-flavor formalism. measure $|\Delta m^{2}_{32}|=[2.28-2.46]\times10^{-3}\mbox{\,eV}^{2}$ (68% C.L.) $\sin^{2}\theta_{23}=0.35-0.65$ (90% normal hierarchy, m^{2}_{32}|=[2.32-2.53]\times10^{-3}\mbox{\,eV}^{2}$ $\sin^{2}\theta_{23}=0.34-0.67$ inverted hierarchy. also constrain $\delta_{CP}$, $\theta_{23}$...
We report on ν(e) and appearance in ν(μ) beams using the full MINOS data sample. The comparison of these at a 735 km baseline with θ13 measurements by reactor experiments probes δ, θ23 octant degeneracy, mass hierarchy. This analysis is first use this technique includes accelerator long-baseline search for → ν(e). Our disfavor 31% (5%) three-parameter space defined θ23, hierarchy 68% (90%) C.L. measure value 2sin(2)(2θ13)sin(2)(θ23) that consistent experiments.
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}.
We report a study of muon neutrino charged-current quasi-elastic events in the segmented scintillator inner tracker MINERvA experiment running NuMI beam at Fermilab. The were selected by requiring {\mu}^- and low calorimetric recoil energy separated from interaction vertex. measure flux-averaged differential cross-section, d{\sigma}/dQ^2, particle content final state. Deviations are found between measured d{\sigma}/dQ^2 expectations model independent nucleons relativistic Fermi gas. also...
We report the results of a search for ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ disappearance by Main Injector Neutrino Oscillation Search [D. G. Michael et al. (MINOS), Phys. Rev. Lett. 97, 191801 (2006).]. The experiment uses two detectors separated 734 km to observe beam neutrinos created Neutrinos at facility Fermi National Accelerator Laboratory. data were collected in first 282 days operations and correspond an exposure $1.27\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons on target....
The weak nucleon axial-vector form factor for quasi-elastic interactions is determined using neutrino interaction data from the K2K Scintillating Fiber detector in beam at KEK. More than 12,000 events are analyzed, of which half charged-current nu-mu n to mu- p occurring primarily oxygen nuclei. We use a relativistic Fermi gas model and assume approximately dipole with one parameter, axial vector mass M_A, fit shape distribution square momentum transfer nucleus. Our best result M_A = 1.20...
Amplitudes derived from scattering data on elementary targets are basic inputs to neutrino-nucleus cross section predictions. A prominent example is the isovector axial nucleon form factor, $F_A(q^2)$, which controls charged current signal processes at accelerator-based neutrino oscillation experiments. Previous extractions of $F_A$ neutrino-deuteron rely a dipole shape assumption that introduces an unquantified error. new analysis world for performed using model-independent, and...
We have isolated muon anti-neutrino charged-current quasi-elastic interactions occurring in the segmented scintillator tracking region of MINERvA detector running NuMI neutrino beam at Fermilab. measure flux-averaged differential cross-section, d{\sigma}/dQ^2, and compare to several theoretical models scattering. Good agreement is obtained with a model where nucleon axial mass, M_A, set 0.99 GeV/c^2 but vector form factors are modified account for observed enhancement, relative free case,...
The velocity of a ∼3 GeV neutrino beam is measured by comparing detection times at the near and far detectors MINOS experiment, separated 734 km. A total 473 detector events was used to measure (v−c)/c=5.1±2.9×10−5 (at 68% C.L.). By correlating energies 258 charged-current their arrival detector, limit imposed on mass mν<50 MeV/c2 (99% C.L.).Received 4 June 2007DOI:https://doi.org/10.1103/PhysRevD.76.072005©2007 American Physical Society
Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on observation of neutral-current interactions, an exposure NuMI beam 7.07×1020 protons target. A total 802 event candidates is observed Far Detector, compared expected number 754±28(stat)±37(syst) among three flavors. The fraction fs disappearing νμ that may transition νs found be less than 22% at 90% C.L.Received 19 April...
Knowledge of the neutrino flux produced by Neutrinos at Main Injector (NuMI) beamline is essential to oscillation and interaction measurements MINERvA, MINOS+, NOvA MicroBooNE experiments Fermi National Accelerator Laboratory. We have a prediction which uses all available relevant hadron production data, incorporating particle off thin targets as well yields from spare NuMI target exposed 120 GeV proton beam. The result most precise achieved for beam in one tens energy region. also compared...
Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current $\nu_\mu$ interactions is combined with muon kinematics to permit separation quasielastic and $\Delta$(1232) resonance processes. First, we observe small cross section at very that matches expected screening effect long-range nucleon correlations. Second, additions event rate...
A search for neutron-antineutron ($n\ensuremath{-}\overline{n}$) oscillation was undertaken in Super-Kamiokande using the 1489 live-day or $2.45\ifmmode\times\else\texttimes\fi{}{10}^{34}$ neutron-year exposure data. This process violates both baryon and minus lepton numbers by an absolute value of two units is predicted a large class hypothetical models where seesaw mechanism incorporated to explain observed tiny neutrino masses matter-antimatter asymmetry Universe. No evidence...
Searches for a light sterile neutrino have been performed independently by the MINOS and Daya Bay experiments using muon (anti)neutrino electron antineutrino disappearance channels, respectively. In this Letter, results from both are combined with those Bugey-3 reactor experiment to constrain oscillations into neutrinos. The three sensitive complementary regions of parameter space, enabling analysis probe allowed Liquid Scintillator Neutrino Detector (LSND) MiniBooNE in minimally extended...
We report results of a search for oscillations involving light sterile neutrino over distances 1.04 and 735 km in ν_{μ}-dominated beam with peak energy 3 GeV. The data, from an exposure 10.56×10^{20} protons on target, are analyzed using phenomenological model one neutrino. constrain the mixing parameters θ_{24} Δm_{41}^{2} set limits four-dimensional Pontecorvo-Maki-Nakagawa-Sakata matrix, |U_{μ4}|^{2} |U_{τ4}|^{2}, under assumption that between ν_{e} ν_{s} is negligible (|U_{e4}|^{2}=0)....
Abstract Scattering of high energy particles from nucleons probes their structure, as was done in the experiments that established non-zero size proton using electron beams 1 . The use charged leptons scattering enables measuring distribution electric charges, which is encoded vector form factors nucleon 2 weakly interacting neutrinos gives opportunity to measure both and axial nucleon, providing an additional, complementary probe structure. transition factor, F A , can be measured neutrino...