M. Dunford
A5025929437- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Particle Detector Development and Performance
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Computational Physics and Python Applications
- Astrophysics and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Distributed and Parallel Computing Systems
- Radiation Detection and Scintillator Technologies
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- advanced mathematical theories
- Advanced Data Storage Technologies
- Particle Accelerators and Free-Electron Lasers
- Black Holes and Theoretical Physics
- Digital Radiography and Breast Imaging
- Quantum, superfluid, helium dynamics
- Muon and positron interactions and applications
- Age of Information Optimization
- Gamma-ray bursts and supernovae
- Model Reduction and Neural Networks
- Superconducting Materials and Applications
- Distributed Sensor Networks and Detection Algorithms
Heidelberg University
2016-2025
Northern Illinois University
2023-2024
Institute for High Energy Physics
2023-2024
Institute of Science and Technology
2023-2024
Kirchhoff (Germany)
2013-2024
A. Alikhanyan National Laboratory
2024
SR Research (Canada)
2024
Federación Española de Enfermedades Raras
2024
Atlas Scientific (United States)
2024
The University of Adelaide
2018-2023
Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using neutral current (NC), elastic scattering, and charged reactions assuming standard 8B shape, nu(e) component solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold 5 MeV. The non-nu(e) phi(mu)(tau) 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) s(-1), 5.3sigma greater than zero, providing strong evidence flavor...
The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra rates. For charged current events, assuming an undistorted 8B spectrum, the minus rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of average rate. If total flux active neutrinos additionally constrained to have no asymmetry, nu(e) asymmetry found be 7.0%+/-4.9%(+1.3%)(-1.2%). A global analysis in terms matter-enhanced oscillations two flavors strongly favors large mixing angle solution.
The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about energy dependence of nu(e) survival probability. measurements were made with dissolved NaCl in heavy water to enhance sensitivity and signature for neutral-current interactions. is found be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), agreement previous standard models. A global analysis these other reactor results yields Deltam(2)=7.1(+1.2)(-0.6)...
Results are reported from the complete salt phase of Sudbury Neutrino Observatory experiment in which NaCl was dissolved D$_2$O target. The addition enhanced signal neutron capture, as compared to pure detector. By making a statistical separation charged-current events other types based on event-isotropy criteria, effective electron recoil energy spectrum has been extracted. In units $ 10^6$ cm$^{-2}$ s$^{-1}$, total flux active-flavor neutrinos $^8$B decay Sun is found be...
We report on a search for neutrinoless double-beta decay of $^{136}$Xe with EXO-200. No signal is observed an exposure 32.5 kg-yr, background ~1.5 x 10^{-3} /(kg yr keV) in the $\pm 1\sigma$ region interest. This sets lower limit half-life $T_{1/2}^{0\nu\beta\beta}$($^{136}$Xe) > 1.6 10$^{25}$ (90% CL), corresponding to effective Majorana masses less than 140-380 meV, depending matrix element calculation.
We report results from a combined analysis of solar neutrino data all phases the Sudbury Neutrino Observatory (SNO). By exploiting particle identification information obtained proportional counters installed during third phase, this improved background rejection in that phase experiment. The SNO resulted total flux active flavors ${}^{8}\mathrm{B}$ decays Sun...
The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate neutral-current interactions in heavy water and precisely determined total active (nu_x) 8B solar neutrino flux. This technique is independent previous methods employed by SNO. flux found be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), agreement with measurements standard models. A global analysis reactor results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 theta=34.4_-1.2;+1.3...
This paper presents a comprehensive review of both the theory and experimental successes Quantum Chromodynamics, starting with its emergence as well defined in 1972-73 following developments results up to present day. Topics include earliest theoretical foundations; fundamental constants QCD; an introductory discussion lattice QCD, only known method for obtaining exact predictions from methods approximating special focus on effective field theories; QCD under extreme conditions; measurements...
The unfolding of detector effects is crucial for the comparison data to theory predictions. While traditional methods are limited representing in a low number dimensions, machine learning has enabled new techniques while retaining full dimensionality. Generative networks like invertible neural networks~(INN) enable probabilistic unfolding, which map individual events their corresponding unfolded probability distribution. accuracy such however by how well simulated training samples model...
Results are reported from a joint analysis of Phase I and II data the Sudbury Neutrino Observatory. The effective electron kinetic energy threshold used is ${T}_{\mathrm{eff}}=3.5$ MeV, lowest yet achieved with water Cherenkov detector data. In units ${10}^{6}$ cm${}^{\ensuremath{-}2}$ ${\mathrm{s}}^{\ensuremath{-}1}$, total flux active-flavor neutrinos $^{8}\mathrm{B}$ decay in Sun measured using neutral current (NC) reaction on deuterons, no constraint neutrino spectrum, found to be...
We report on an improved measurement of the $2\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$ half-life ${}^{136}$Xe performed by EXO-200. The use a large and homogeneous time-projection chamber allows for precise estimate fiducial mass used measurement, resulting in small systematic uncertainty. also discuss detail data-analysis methods double-$\ensuremath{\beta}$ decay searches with EXO-200, while emphasizing those directly related to present measurement. is found be...
EXO-200 is an experiment designed to search for double beta decay of $^{136}$Xe with a single-phase, liquid xenon detector. It uses active mass 110 kg enriched 80.6% in the isotope 136 ultra-low background time projection chamber capable simultaneous detection ionization and scintillation. This paper describes detector particular attention most innovative aspects design that revolve around reduction backgrounds, efficient use expensive isotopically xenon, optimization energy resolution...
This article provides the complete description of results from Phase I data set Sudbury Neutrino Observatory (SNO). The is based on a 0.65 kiloton-year exposure ${}^{2}{\mathrm{H}}_{2}$O (in following denoted as ${\mathrm{D}}_{2}$O) to solar $^{8}\mathrm{B}$ neutrino flux. Included here are details SNO physics and detector model, evaluations systematic uncertainties, estimates backgrounds. Also discussed SNO's approach statistical extraction signals three reactions (charged current, neutral...
This paper details the solar neutrino analysis of 385.17-day Phase-III data set acquired by Sudbury Neutrino Observatory (SNO). An array $^3$He proportional counters was installed in heavy-water target to measure precisely rate neutrino-deuteron neutral-current interactions. technique determine total active $^8$B flux largely independent methods employed previous phases. The neutrinos measured be $5.54^{+0.33}_{-0.31}(stat.)^{+0.36}_{-0.34}(syst.)\times 10^{6}$ cm$^{-2}$ s$^{-1}$, consistent...
Neutron-antineutron oscillations in nature would violate baryon number and indicate a potential underlying mechanism for the observed matter-antimatter asymmetry. Sudbury Neutrino Observatory reports limits on neutron-antineutron first time deuteron. These establish important constraints beyond-the-Standard-Model scenarios that involve baryon-number violation.
As the LHC luminosity is ramped up to 3 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$\,\times 10^{34}~{\hbox {cm}}^{2}~s^{1}$</tex></formula> and beyond, high rates, multiplicities, energies of particles seen by detectors will pose a unique challenge. Only tiny fraction produced collisions can be stored offline immense real-time data reduction needed. An effective trigger system must maintain...
The long baseline between Earth and the Sun makes solar neutrinos an excellent test beam for exploring possible neutrino decay. signature of such decay would be energy-dependent distortion traditional survival probability which can fit using well-developed high-precision analysis methods. Here a model including is to all three phases 8B data taken by Sudbury Neutrino Observatory (SNO). This constrains lifetime mass state ν2 >8.08×10−5 s/eV at 90% confidence. An combining this SNO result with...
A search has been made for neutrinos from the hep reaction in Sun and diffuse supernova neutrino background (DSNB) using data collected during first operational phase of Sudbury Neutrino Observatory, with an exposure 0.65 kilotonne-years. For search, two events are observed effective electron energy range 14.3 MeV <T_eff< 20 where 3.1 expected. After accounting oscillations, upper limit 2.3x10^4 cm^-2s^-1 at 90% confidence level is inferred on integral total flux neutrinos. DSNB neutrinos,...
A search has been made for sinusoidal periodic variations in the $^8$B solar neutrino flux using data collected by Sudbury Neutrino Observatory over a 4-year time interval. The variation at period of one year is consistent with modulation Earth's orbital eccentricity. No significant periodicities are found periods between 1 day and 10 years either an unbinned maximum likelihood analysis or Lomb-Scargle periodogram analysis. inconsistent hypothesis that results recent Sturrock et al., based...
Results are reported on the measurement of atmospheric neutrino-induced muon flux at a depth 2 kilometers below Earth's surface from 1229 days operation Sudbury Neutrino Observatory (SNO). By measuring through-going muons as function zenith angle, SNO experiment can distinguish between oscillated and unoscillated portion neutrino flux. A total 514 muonlike events measured $\ensuremath{-}1\ensuremath{\le}\mathrm{cos}{\ensuremath{\theta}}_{\mathrm{zenith}}\ensuremath{\le}0.4$ in exposure...
The search for neutrinoless double-beta decay (0νββ) requires extremely low background and a good understanding of their sources influence on the rate in region parameter space relevant to 0νββ signal. We report studies various β γ backgrounds liquid-xenon-based EXO-2000νββ experiment. With this work we try better understand location strength specific compare conclusions radioassay results taken before during detector construction. Finally, discuss implications these EXO-200 as well...
Data from the Sudbury Neutrino Observatory have been used to constrain lifetime for nucleon decay ``invisible'' modes, such as $n\ensuremath{\rightarrow}3\ensuremath{\nu}$. The analysis was based on a search $\ensuremath{\gamma}$ rays deexcitation of residual nucleus that would result disappearance either proton or neutron $^{16}\mathrm{O}$. A limit ${\ensuremath{\tau}}_{\mathrm{inv}}>2\ifmmode\times\else\texttimes\fi{}{10}^{29}\text{ }\text{ }\mathrm{yr}$ is obtained at 90% confidence...
Upper limits on the ${\overline{\ensuremath{\nu}}}_{e}$ flux at Sudbury Neutrino Observatory have been set based charged-current reaction deuterium. The produces a positron and two neutrons in coincidence. This distinctive signature allows search with very low background for ${\overline{\ensuremath{\nu}}}_{e}$'s from Sun other potential sources. Both differential integral placed energy range 4--14.8 MeV. For an energy-independent...
Experimental tests of Lorentz symmetry in systems all types are critical for ensuring that the basic assumptions physics well founded. Data from phases Sudbury Neutrino Observatory, a kiloton-scale heavy water Cherenkov detector, analyzed possible violations neutrino sector. Such would appear as one eight signal detector: six seasonal variations solar electron survival probability differing energy and time dependence two shape changes to oscillated spectrum. No evidence such signals is...
We have performed three searches for high-frequency signals in the solar neutrino flux measured by Sudbury Neutrino Observatory (SNO), motivated possibility that $g$-mode oscillations could affect production or propagation of $^8$B neutrinos. The first search looked any significant peak frequency range 1/day to 144/day, with a sensitivity sinusoidal amplitudes 12% greater. second focused on regions which been claimed experiments aboard SoHO satellite, and was sensitive 10% third extra power...