A5018785418- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Muon and positron interactions and applications
- Astrophysics and Cosmic Phenomena
- Particle accelerators and beam dynamics
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Quantum Chromodynamics and Particle Interactions
- Radiation Detection and Scintillator Technologies
- High-Energy Particle Collisions Research
- Superconducting Materials and Applications
- Particle Accelerators and Free-Electron Lasers
- Scientific Research and Discoveries
- Atomic and Molecular Physics
- Thermodynamic and Structural Properties of Metals and Alloys
- International Science and Diplomacy
- Scientific Computing and Data Management
- Atomic and Subatomic Physics Research
- Distributed and Parallel Computing Systems
- Advanced Condensed Matter Physics
- Nuclear reactor physics and engineering
- Cold Atom Physics and Bose-Einstein Condensates
- Nuclear physics research studies
- Physics of Superconductivity and Magnetism
- Electrostatic Discharge in Electronics
Queen's University
2024
University of Glasgow
2014-2024
Laurentian University
2018-2024
Campbell Collaboration
2018-2023
Uppsala University
2018
TRIUMF
2005-2015
Rutherford Appleton Laboratory
2013
Fermi National Accelerator Laboratory
2013
University of Saskatchewan
2011
University of Alberta
2009
Lepton family number violation is tested by searching for $\mu^+\to e^+X^0$ decays among the 5.8$\times 10^8$ positive muon decay events analyzed TWIST collaboration. Limits are set on production of both massless and massive $X^0$ bosons. The large angular acceptance this experiment allows limits to be placed anisotropic decays, which can arise from interactions violating lepton flavor parity conservation. Branching ratio order $10^{-5}$ obtained bosons with masses 13 - 80 MeV/c$^2$...
In June 2012, an Expression of Interest for a long-baseline experiment (LBNO) has been submitted to the CERN SPSC. LBNO considers three types neutrino detector technologies: double-phase liquid argon (LAr) TPC and magnetised iron as far detectors. For near detector, high-pressure gas embedded in calorimeter magnet is baseline design. A mandatory milestone concrete prototyping effort towards envisioned large-scale detectors, accompanying campaign measurements aimed at assessing associated...
A measurement of the $^{8}\mathrm{B}$ solar neutrino flux has been made using a 69.2 kt-day dataset acquired with $\mathrm{SNO}+$ detector during its water commissioning phase. At energies above 6 MeV is an extremely pure sample elastic scattering events, owing primarily to detector's deep location, allowing accurate relatively little exposure. In that energy region best fit background rate $0.2{5}_{\ensuremath{-}0.07}^{+0.09}\text{ }\text{...
The direction of individual <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mmultiscripts><a:mrow><a:mi mathvariant="normal">B</a:mi></a:mrow><a:mprescripts/><a:none/><a:mrow><a:mn>8</a:mn></a:mrow></a:mmultiscripts></a:mrow></a:math> solar neutrinos has been reconstructed using the <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"><d:mrow><d:mi>SNO</d:mi><d:mo>+</d:mo></d:mrow></d:math> liquid scintillator detector. Prompt, directional...
A facility that can deliver beams of electron and muon neutrinos from the decay a stored beam has potential to unambiguously resolve issue evidence for light sterile arises in short-baseline neutrino oscillation experiments estimates effective number flavors fits cosmological data. In this paper, we show nuSTORM facility, with muons $3.8\text{ }\mathrm{GeV}/\mathrm{c}\text{ }\ifmmode\pm\else\textpm\fi{}\text{ }10%$, will be able carry out conclusive appearance search test LSND MiniBooNE...
This paper reports results from a search for nucleon decay through invisible modes, where no visible energy is directly deposited during the itself, initial water phase of $\mathrm{SNO}+$. However, such decays within oxygen nucleus would produce an excited daughter that subsequently deexcite, often emitting detectable gamma rays. A rays yields limits $2.5\ifmmode\times\else\texttimes\fi{}{10}^{29}\text{ }\text{ }\mathrm{y}$ at 90% Bayesian credibility level (with prior uniform in rate)...
The TWIST Collaboration has completed a new measurement of the energy-angle spectrum positrons from decay highly polarized muons. A simultaneous muon parameters ρ, δ, and P(μ)(π)ξ tests standard model in purely leptonic process provides improved limits for relevant extensions to model. Specifically, generalized left-right symmetric |(g(R)/g(L))ζ|<0.020 (g(L)/g(R))m(2)>578 GeV/c(2), both 90% C.L.
The TWIST Collaboration has measured the Michel parameter rho in normal muon decay, mu(+)--> e(+)nu(e)nu (mu). In standard model, = 3/4. Deviations from this value imply mixing of left- and right-handed electron couplings. We find rho=0.750 80+/-0.000 32(stat) +/- 0.000 97(syst) 23, where last uncertainty represents dependence on eta. This result sets new limits W(L)-W(R) angle left-right symmetric models.
We present a new high precision measurement of parity violation in the weak interaction, using polarized muon decay. The TWIST collaboration has measured $P_\mu^\pi \xi$, where $P_\mu^\pi$ is polarization pion decay and $\xi$ describes intrinsic asymmetry find \xi = 1.00084 \pm 0.00029\,(\textrm{stat.})_{-0.00063}^{+0.00165}\,(\textrm{syst.})$, good agreement with standard model prediction $P_\mu^\pi=\xi=1$. Our result factor 7 more precise than pre-TWIST value, setting limits left-right...
The TWIST Collaboration has completed its measurement of the three muon decay parameters \rho, \delta, and P_\mu\xi. This paper describes our determination which governs shape overall momentum spectrum, controls dependence parity-violating asymmetry. results are \rho=0.74977\pm 0.00012(stat.)\pm 0.00023(syst.) \delta = 0.75049\pm 0.00021(stat.)\pm 0.00027(syst.). These consistent with value 3/4 given for both in standard model, each is over a factor 10 more precise than measurements...
The muon decay parameter delta has been measured by the TWIST collaboration. We find = 0.74964 +- 0.00066(stat.) 0.00112(syst.), consistent with Standard Model value of 3/4. This result implies that product Pmuxi polarization in pion decay, Pmu, and xi falls within 90% confidence interval 0.9960 < 1.0040. It also implications for left-right-symmetric other extensions Model.
A novel single-particle technique to measure emittance has been developed and used characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The beams, whose mean momenta vary from 171 281 MeV/c, have emittances of approximately 1.5--2.3 \pi mm-rad horizontally 0.6--1.0 vertically, a horizontal dispersion 90--190 mm momentum spreads about 25 MeV/c. There is reasonable agreement between measured parameters results simulations. are found meet requirements MICE.
Abstract Accelerated muon beams have been considered for the next-generation studies of high-energy lepton–antilepton collisions and neutrino oscillations. However, high-brightness not yet produced. The main challenge acceleration storage stems from large phase-space volume occupied by beam, derived production mechanism muons through decay pions. beam can be decreased ionization cooling. Here we show that cooling leads to a reduction in transverse emittance traverse lithium hydride or liquid...
This article reviews the current status of nuSTORM facility and shows how it can be utilized to perform next step on path toward realization a μ + − collider. review includes physics motivation behind nuSTORM, detailed description neutrino beams produce, summary short-baseline oscillation program that carried out at facility. The basic idea for (the production from decay muons in racetrack-like ring) was discussed literature more than 30 years ago context searching noninteracting (sterile)...
The TWIST Collaboration has performed new measurements of two the parameters that describe muon decay: $\ensuremath{\rho}$, which governs shape overall momentum spectrum, and $\ensuremath{\delta}$, dependence parity-violating decay asymmetry. This analysis gives results $\ensuremath{\rho}=0.750\text{ }14\ifmmode\pm\else\textpm\fi{}0.000\text{ }17(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.000\text{ }44(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}0.000\text{ }11(\ensuremath{\eta})$, where last...
The nuSTORM facility has been designed to deliver beams of electron neutrinos and muon (and their anti-particles) from the decay a stored beam with central momentum 3.8 GeV/c acceptance 10%. is unique in that it will: 1. Allow searches for sterile exquisite sensitivity be carried out; 2. Serve future long- short-baseline neutrino-oscillation programs by providing definitive measurements neutrino scattering cross sections off nuclei percent-level precision; 3. Constitutes crucial first step...
The nuSTORM facility has been designed to deliver beams of electron and muon neutrinos from the decay a stored beam with central momentum 3.8 GeV/c spread 10%. is unique in that it will: serve future long- short-baseline neutrino-oscillation programmes by providing definitive measurements electron-neutrino- muon-neutrino-nucleus cross sections percent-level precision; allow searches for sterile exquisite sensitivity be carried out; constitute essential first step incremental development...
The quantity P_{mu}^{pi}xi, where xi is one of the muon decay parameters and $P_{\mu}^{\pi}$ degree polarization in pion decay, has been measured. value P_{mu}^{pi}xi = 1.0003 +- 0.0006 stat. 0.0038 syst. was obtained. This result agrees with previous measurements but over a factor two more precise. It also Standard Model prediction for thus leads to restrictions on left-right symmetric models.
This paper describes the performance and sensitivity to neutrino mixing parameters of a Magnetised Iron Neutrino Detector (MIND) at Factory with beam created from decay 10 GeV muons. Specifically, it is concerned ability such detector detect muons opposite sign those stored (wrong-sign muons) while suppressing contamination signal interactions other species in beam. A new more realistic simulation analysis, which improves efficiency this low energies, has been developed using GENIE event...
The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility technique. To carry out this program, MICE requires an efficient particle-identification (PID) system identify muons. Electron-Muon Ranger (EMR) is fully-active tracking-calorimeter that forms part PID and tags muons traverse channel without decaying. detector capable identifying electrons with efficiency 98.6%, providing purity for beam exceeds 99.8%. EMR also proved...
The international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams momentum between 140 and 240\,MeV/c at the Rutherford Appleton Laboratory ISIS facility. measurement in MICE relies on selection pure sample muons that traverse experiment. To make this selection, Beam is designed to deliver beam less than $\sim$1\% contamination. final employs particle-identification (PID) system upstream downstream cell. PID includes...
We present the first measurement of energy spectrum up to 70 MeV electrons from decay negative muons after they become bound in 27Al atoms. The data were taken with TWIST apparatus at TRIUMF. find a muon lifetime (864.6±1.2) ns, agreement earlier measurements. asymmetry is consistent zero, indicating that atomic capture has completely depolarized muons. measured momentum reasonable theoretical predictions higher energies, but differences around peak indicate need for O(α) radiative...
The time dependence of muon spin relaxation has been measured in high purity aluminum and silver samples a longitudinal 2 T magnetic field at room temperature, using time-differential \musr. For times greater than 10 ns, the shape fits well to single exponential with rates $\lambda_{\textrm{Al}} = 1.3 \pm 0.2\,(\textrm{stat.}) 0.3\,(\textrm{syst.})\,\pms$ $\lambda_{\textrm{Ag}} 1.0 0.2\,(\textrm{syst.})\,\pms$.
The properties of the neutrino provide a unique window on physics beyond that described by standard model. study subleading effects in oscillations, and race to discover CP-invariance violation lepton sector, has begun with recent discovery ${\ensuremath{\theta}}_{13}>0$. measured value ${\ensuremath{\theta}}_{13}$ is large, emphasizing need for facility at which systematic uncertainties can be reduced percent level. factory, intense beams are produced from decay muons, been shown outperform...