T. R. Junk
A5032361857- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Astrophysics and Cosmic Phenomena
- Nuclear physics research studies
- Particle Accelerators and Free-Electron Lasers
- Black Holes and Theoretical Physics
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Particle accelerators and beam dynamics
- Medical Imaging Techniques and Applications
- Radiation Therapy and Dosimetry
- Distributed and Parallel Computing Systems
- Quantum, superfluid, helium dynamics
- Nuclear Physics and Applications
- Magnetic confinement fusion research
- Innovation Diffusion and Forecasting
- Advanced Operator Algebra Research
- Data Management and Algorithms
- Aerosol Filtration and Electrostatic Precipitation
Fermi National Accelerator Laboratory
2016-2025
University of California, Los Angeles
2012-2014
National and Kapodistrian University of Athens
2011-2014
Children's Defense Fund
2012-2014
University of Illinois Urbana-Champaign
2003-2013
Carleton University
2002-2012
Argonne National Laboratory
2011-2012
Institute for High Energy Physics
2010-2011
Institució Catalana de Recerca i Estudis Avançats
2011
Universitat Autònoma de Barcelona
2010-2011
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for pair-produced charged Higgs bosons in the framework of Two Doublet Models (2HDMs). data experiments been statistically combined. results are interpreted within 2HDM Type I II benchmark scenarios. No significant excess has observed when compared to Standard Model background prediction, combined exclude large regions model parameter space. Charged with mass below 80 \({\rm GeV}/c^{2}\) (Type scenario) or 72.5 scenario,...
We report test beam studies of 11% the production ATLAS Tile Calorimeter modules. The modules were equipped with front-end electronics and all calibration systems planned for final detector. used muon, electron hadron beams ranging in energy from 3 to 350 GeV. Two independent showed that light yield calorimeter was ∼70pe/GeV, exceeding design goal by 40%. Electron provided a at electromagnetic scale. Over 200 cells variation response 2.4%. linearity also measured. Muon an intercalibration...
We present a precise measurement of the left-right cross section asymmetry (${A}_{\mathrm{LR}}$) for $Z$ boson production by ${e}^{+}{e}^{\ensuremath{-}}$ collisions. The was performed at center-of-mass energy 91.26 GeV with SLD detector SLAC Linear Collider (SLC). luminosity-weighted average polarization SLC electron beam (63.0 \ifmmode\pm\else\textpm\fi{} 1.1)%. Using sample 49 392 decays, we measure ${A}_{\mathrm{LR}}$ to be 0.1628 0.0071 (stat) 0.0028 (syst) which determines effective...
We have measured the differential production cross sections as a function of scaled momentum x_p=2p/E_cm identified hadron species pi+, K+, K0, K*0, phi, p, Lambda0, and corresponding antihadron in inclusive hadronic Z0 decays, well separately for decays into light (u, d, s), c b flavors. Clear flavor dependences are observed, consistent with expectations based upon previously decay properties heavy hadrons. These results were used to test QCD predictions Gribov Lipatov, Modified Leading...
Abstract In this paper, we review scientific opportunities and challenges related to detection reconstruction of low-energy (less than 100 MeV) signatures in liquid argon time-projection chamber (LArTPC) neutrino detectors. LArTPC detectors designed for performing precise long-baseline oscillation measurements with GeV-scale accelerator beams also have unique sensitivity a range physics astrophysics via event features at below the few tens MeV range. addition, are an integral part...
The strong coupling αs(M2Z) has been measured using hadronic decays of Z0 bosons collected by the SLD experiment at SLAC. data were compared with QCD predictions both fixed order O(α2s) and including resummed analytic formulas based on next-to-leading logarithm approximation. In this comprehensive analysis we studied event shapes, jet rates, particle correlations, angular energy flow, checked consistency between values extracted from these different measures. Combining all results obtain...
Hadronic event shape distributions from e+e− annihilation measured by the OPAL experiment at centre-of-mass energies between 91 GeV and 209 are used to determine strong coupling α S. The results based on QCD predictions complete next-to-next-to-leading order (NNLO), NNLO calculations matched resummed next-to-leading-log-approximation terms (NNLO + NLLA). combined result all variables is while NLLA completeness of with respect missing higher contributions, studied varying renormalization...
SBND is the near detector of Short-Baseline Neutrino program at Fermilab. Its location to Booster Beam source and relatively large mass will allow study neutrino interactions on argon with unprecedented statistics. This paper describes expected performance photon detection system, using a simulated sample beam neutrinos cosmogenic particles. design dual readout concept combining system 120 photomultiplier tubes, used for triggering, 192 X-ARAPUCA devices, located behind anode wire planes....
We present measurements of ${\mathit{R}}_{\mathit{b}}$ using the SLD at SLC. The analyses use 2D and 3D impact parameter tags a displaced vertex tag which all exploit small size stability ${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$ interaction point precision CCD pixel detector to achieve high bb\ifmmode\bar\else\textasciimacron\fi{}-tagging efficiencies purities. combined measurement yields ${\mathit{R}}_{\mathit{b}}$=0.229\ifmmode\pm\else\textpm\fi{}0.011 is consistent with...
A search for stable and long-lived massive particles of electric charge |Q/e|=1 or fractional charges 2/3, 4/3, 5/3 is reported using data collected by the OPAL detector at LEP, centre-of-mass energies from 130 to 209 GeV. These are assumed be pair-produced in e+e− collisions not interact strongly. No evidence production these was observed. Model-independent upper limits on cross-section between 0.005 0.028 pb have been derived scalar spin-1/2 with ±1. Within framework Constrained Minimal...
We report a new measurement of Rb = Gamma(Z0->b-bbar) / Gamma(Z0->hadrons) using double tag technique, where the b hemisphere selection is based on reconstructed mass B hadron decay vertex. The was performed sample 130k hadronic Z0 events, collected with SLD at SLC. method utilizes 3-D vertexing abilities CCD pixel vertex detector and small stable SLC beams to obtain high b-tagging efficiency purity. Rb=0.2142+/-0.0034(stat.)+/-0.0015(syst.)+/-0.0002(R_c).
Anomalous quartic couplings between the electroweak gauge bosons may contribute to $\ensuremath{\nu}\overline{\ensuremath{\nu}}\ensuremath{\gamma}\ensuremath{\gamma}$ and $q\overline{q}\ensuremath{\gamma}\ensuremath{\gamma}$ final states produced in ${e}^{+}{e}^{\ensuremath{-}}$ collisions. This analysis uses LEP2 OPAL data sample at center-of-mass energies up 209 GeV. Event selections identify events which two photons are reconstructed within detector acceptance. The cross section for...
The search for Higgs bosons in both the standard model and its extensions is well under way at Tevatron. As integrated luminosity collected increases into multiple inverse femptobarn range, these searches are becoming very interesting indeed. Meanwhile, construction of Large Hadron Collider (LHC) associated experiments CERN nearing completion. In this TeV4LHC workshop, it was realized that any experience Tevatron with respect to backgrounds, experimental techniques theoretical calculations...
Abstract A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected OPAL experiment at $\sqrt{s}=189\mbox{--}209\ \mbox{GeV}$ , corresponding to an integrated luminosity approximately 600 pb −1 . Charged are assumed be pair-produced and decay into $\mathrm{q} \bar{\mathrm{q}}$ τν τ or AW ± No signal observed. Model-independent limits on Higgs-boson production cross section derived combining...
Recently, much attention has been focused on the replicability of scientific results, causing scientists, statisticians, and journal editors to examine closely their methodologies publishing criteria. Experimental particle physicists have aware precursors non-replicable research for many decades safeguards ensure that published results are as reliable possible. The experiments require large investments time effort design, construct, operate. Large collaborations produce check papers signed...
We present a new measurement of the left-right cross section asymmetry $({A}_{\mathrm{LR}})$ for $Z$ boson production by ${e}^{+}{e}^{\ensuremath{-}}$ collisions. The was performed at center-of-mass energy 91.28 GeV with SLD detector SLAC Linear Collider (SLC). luminosity-weighted average polarization SLC electron beam $(77.23\ifmmode\pm\else\textpm\fi{}0.52)%$. Using sample 93 644 decays, we measure pole value asymmetry, ${A}_{\mathrm{LR}}^{0}$, to be...
A search for the single production of doubly-charged Higgs bosons is performed using e+e− collision data collected by OPAL experiment at centre-of-mass energies between 189 GeV and 209 GeV. No evidence existence H±± observed. Upper limits are derived on hee, Yukawa coupling to like-signed electron pairs. 95% confidence level upper limit hee< 0.071 inferred M(H±±)<160 assuming that sum branching fractions all lepton flavour combinations 100%. Additionally, indirect constraints hee from Bhabha...
This letter describes a direct search for pair produced magnetic monopoles in e+e- collisions. The analysis is based on 62.7 pb^-1 of data collected with the OPAL detector at an average centre-of-mass energy sqrt(s)= 206.3GeV. monopole signal was assumed to be characterized by two back-to-back particles anomalously high ionization loss de/dx tracking chambers. No evidence production observed. Upper limits were obtained pair-production cross-section (sigma) mass range 45 GeV/c^2
Non-commutative QED would lead to deviations from the Standard Model depending on a new energy scale Lambda_NC and unique direction in space defined by two angles eta xi. Here this analysis is as angle between rotation axis of earth. The predictions such theory for process e+e- -> gamma are evaluated specific orientation OPAL detector compared measurements. Distributions polar azimuthal scattering used extract limits model parameter eta. At 95% confidence level found be larger than 141 GeV...