L. Demortier
A5060303062- 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
- Cosmology and Gravitation Theories
- Neutrino Physics Research
- Computational Physics and Python Applications
- Black Holes and Theoretical Physics
- Astrophysics and Cosmic Phenomena
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Superconducting Materials and Applications
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Statistical Methods and Inference
- Statistical Mechanics and Entropy
- Particle accelerators and beam dynamics
- Muon and positron interactions and applications
- Statistical Methods and Bayesian Inference
- Nuclear reactor physics and engineering
- Distributed and Parallel Computing Systems
- Scientific Measurement and Uncertainty Evaluation
- Nuclear Physics and Applications
- Radiation Therapy and Dosimetry
Rockefeller University
2011-2022
University of Glasgow
2012-2019
Institute of High Energy Physics
2010-2017
National and Kapodistrian University of Athens
2011-2017
University of California, Los Angeles
2005-2017
University of Rochester
2000-2015
European Organization for Nuclear Research
2012-2014
Rutgers, The State University of New Jersey
2014
Istituto Nazionale di Fisica Nucleare, Sezione di Padova
2014
Children's Defense Fund
1998-2013
We establish the existence of top quark using a 67 pb^-1 data sample Pbar-P collisions at Sqrt(s) = 1.8 TeV collected with Collider Detector Fermilab (CDF). Employing techniques similar to those we previously published, observe signal consistent t-tbar decay WW b-bbar, but inconsistent background prediction by 4.8 sigma. Additional evidence for is provided peak in reconstructed mass distribution. measure be 176 +/-8(stat) +/- 10(sys.) GeV/c^2, and production cross section 6.8 +3.6 -2.4 pb.
We present the results of a search for top quark in 19.3 pb−1 p¯p collisions at √s =1.8 TeV. The data were collected Fermilab Tevatron collider using Collider Detector (CDF). includes standard model tt¯ decays to final states eeνν¯, eμνν¯, and μμνν¯ as well e+ν+jets or μ+ν+jets. In (e,μ)+ν+jets channel we b quarks from t via secondary vertex identification semileptonic cascade c quarks. dilepton find two events with background 0.56+0.25−0.13 events. e,μ+ν+jets identified vertex, six 2.3±0.3....
The mass of the W boson, a mediator weak force between elementary particles, is tightly constrained by symmetries standard model particle physics. Higgs boson was last missing component model. After observation measurement provides stringent test We measure mass, MW, using data corresponding to 8.8 inverse femtobarns integrated luminosity collected in proton-antiproton collisions at 1.96 tera-electron volt center-of-mass energy with CDF II detector Fermilab Tevatron collider. A sample...
We summarize a search for the top quark with Collider Detector at Fermilab (CDF) in sample of p¯p collisions √s =1.8 TeV an integrated luminosity 19.3 pb−1. find 12 events consistent either two W bosons, or boson and least one b jet. The probability that measured yield is background 0.26%. Though statistics are too limited to establish firmly existence quark, natural interpretation excess it due tt¯ production. Under this assumption, constrained fits individual mass 174±10+13−12 GeV/c2....
We have observed bottom-charm mesons B_c via the decay mode Bc -> J/psi lepton neutrino in 1.8 TeV p-bar p collisions using CDF detector at Fermilab Tevatron. A fit of background and signal contributions to + mass distribution yielded 20.4 +6.2 -5.5 events from mesons. same with alone was rejected level 4.8 standard deviations. measured be 6.40 +- 0.39 0.13 GeVc^2 lifetime tau(B_c) = 0.46 +0.18 -0.16 0.03 ps. production cross section times branching ratio for relative that B+ K 0.132 +0.041...
We present a study of $J/\ensuremath{\psi}$ and $\ensuremath{\psi}(2S)$ production in $p\overline{p}$ collisions, at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ with the CDF detector Fermilab. The mesons are reconstructed using their ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ decay modes. have measured inclusive cross section for both as function transverse momentum central region, $|\ensuremath{\eta}|<0.6$. also measure fraction these events...
The production and event topology of three-jet events produced in p¯p collisions at √s=1.8 TeV have been studied with the Collider Detector Fermilab Tevatron Collider. distributions angular variables (ψ∗ cosθ∗) describing energy sharing between jets (x3 x4) are found to agree well tree-level QCD calculations. These predicted different shapes for initial-state subprocesses (quark-antiquark, quark-gluon, gluon-gluon). data consistent small expected contribution from quark-antiquark initial...
A strong signal for double parton (DP) scattering is observed in a $16{\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$ sample of $\overline{p}p\ensuremath{\rightarrow}\ensuremath{\gamma}/{\ensuremath{\pi}}^{0}+3\mathrm{jets}+X$ data from the CDF experiment at Fermilab Tevatron. In DP events, two separate hard scatterings take place single $\overline{p}p$ collision. We isolate large $(\ensuremath{\sim}14000\mathrm{events})$ which 53% are found to be DP. The process-independent parameter scattering,...
We have measured the fraction of $J/\ensuremath{\psi}$ mesons originating from ${\ensuremath{\chi}}_{c}$ meson decays in $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$. The fraction, for ${P}_{T}^{J/\ensuremath{\psi}}>4.0\mathrm{GeV}/c$ and $|{\ensuremath{\eta}}^{J/\ensuremath{\psi}}|<0.6$, not including contributions $b$ flavored hadrons, is...
Inclusive J/\ensuremath{\psi} and \ensuremath{\psi}(2S) production has been studied in p\ifmmode\bar\else\textasciimacron\fi{}p collisions at \ensuremath{\surd}s =1.8 TeV using 2.6\ifmmode\pm\else\textpm\fi{}0.2 ${\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$ of data taken with the Collider Detector Fermilab. The products cross section times branching fraction were measured as functions ${\mathit{P}}_{\mathit{T}}$ for...
We report the observation of bottom-charmed mesons ${B}_{c}$ in 1.8 TeV $p\overline{p}$ collisions using CDF detector at Fermilab Tevatron. The were found through their semileptonic decays, ${B}_{c}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}J/\ensuremath{\psi}{l}^{\ifmmode\pm\else\textpm\fi{}}X.$ A fit to $J/\ensuremath{\psi}l$ mass distribution yielded ${20.4}_{\ensuremath{-}5.5}^{+6.2}$ events from mesons. test null hypothesis, i.e., an attempt data with background alone, was...
We present measurements of the pseudorapidity (η) distribution charged particles (dNchdη) produced within |η|≤3.5 in proton-antiproton collisions at √s 630 and 1800 GeV. measure dNchdη η=0 to be 3.18±0.06(stat)±0.10(syst) GeV, 3.95±0.03 (stat)±0.13(syst) Many systematic errors ratio two energies cancel, we 1.26±0.01±0.04 for GeV that |η|≤3. Comparing lower-energy data, observe an increase faster than ln(s) η=0.Received 2 October 1989DOI:https://doi.org/10.1103/PhysRevD.41.2330©1990 American...
The inclusive jet differential cross section has been measured for transverse energies, ET, from 15 to 440 GeV, in the pseudorapidity region 0.1≤|η|≤0.7. results are based on 19.5pb−1 of data collected by CDF Collaboration at Fermilab Tevatron collider. compared with QCD predictions various sets parton distribution functions. jets ET>200GeV is significantly higher than current O(αs3) perturbative calculations. Various possible explanations high- ET excess discussed.Received 25 January...
We present new measurements of the inclusive forward-backward ttbar production asymmetry, AFB, and its dependence on several properties system. The are performed with full Tevatron data set recorded CDF II detector during ppbar collisions at sqrt(s) = 1.96 TeV, corresponding to an integrated luminosity 9.4 fb^(-1). measure asymmetry using rapidity difference Delta-y=y_(t)-y_(tbar). Parton-level results derived, yielding 0.164+/-0.047 (stat + syst). observe a linear AFB top-quark pair mass...
We report a measurement of the proton-antiproton total cross section ${\mathrm{\ensuremath{\sigma}}}_{\mathit{T}}$ at c.m.s. energies \ensuremath{\surd}s =546 and 1800 GeV. Using luminosity-independent method, we find ${\mathrm{\ensuremath{\sigma}}}_{\mathit{T}}$=61.26\ifmmode\pm\else\textpm\fi{}0.93 mb GeV 80.03\ifmmode\pm\else\textpm\fi{}2.24 =1800 In this energy range, ratio ${\mathrm{\ensuremath{\sigma}}}_{\mathrm{el}}$/${\mathrm{\ensuremath{\sigma}}}_{\mathit{T}}$ increases from...
Measurements of inclusive transverse-momentum spectra for charged particles produced in proton-antiproton collisions at √2 630 and 1800 GeV are presented compared with data taken lower energies.Received 8 June 1988DOI:https://doi.org/10.1103/PhysRevLett.61.1819©1988 American Physical Society
Kinematic properties of four-jet events produced in $p\overline{p}$ collisions at $\sqrt{s}=1.8$ TeV have been studied using data with an integrated luminosity 325 ${\mathrm{nb}}^{\ensuremath{-}1}$ collected the Collider Detector Fermilab during 1988-1989 run. The individual jet ${p}_{T}$ spectra and angles between each pair are compared to predictions leading-order quantum chromodynamics for double gluon bremsstrahlung process good agreement is observed. In addition, a search parton...
We have measured the $W$-boson mass ${M}_{W}$ using data corresponding to $2.2\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity collected in $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\mathrm{TeV}$ with CDF II detector Fermilab Tevatron collider. Samples consisting 470 126 $W\ensuremath{\rightarrow}e\ensuremath{\nu}$ candidates and 624 708 $W\ensuremath{\rightarrow}\ensuremath{\mu}\ensuremath{\nu}$ yield measurement ${M}_{W}=80\text{...
A search for the top quark in p\ifmmode\bar\else\textasciimacron\fi{}p collisions at a center-of-mass energy of 1.8 TeV using Collider Detector Fermilab is described. study events selected by requiring an energetic electron, missing transverse energy, and two or more jets excludes 95% confidence level standard-model production decay tt\ifmmode\bar\else\textasciimacron\fi{} pairs if top-quark mass between 40 77 GeV/${c}^{2}$. The observed electron + multijet data are consistent with W-boson...
We have analyzed events with jets and large missing transverse energy produced in p¯p colisions at √s =1.8 TeV. The observed event rate is consistent standard model predictions. In a version of the supersymmetry (SUSY) light photino (mγ̃<15 GeV/c2) no cascade decays, we exclude 90% confidence level existence squarks gluinos masses less than 126 141 GeV/c2, respectively. mass limits are lower other choices SUSY parameters. An example presented.Received 17 August...
We have searched for heavy neutral gauge bosons (Z′) in dielectron and dimuon decay modes using 110pb−1 of ¯pp collisions at √s=1.8TeV collected with the Collider Detector Fermilab. present a limit on production cross section times branching ratio Z′ boson decaying into dileptons as function mass. For mass MZ′>600GeV/c2, upper is 40 fb 95% confidence level. set lower limits 690, 590, 620, 595, 565, 630, 600GeV/c2 Z′SM, Zψ, Zη, Zχ, ZI, ZLR, ZALRM, respectively.Received 6 May...
Antiproton-proton elastic scattering was measured at c.m.s. energies √s =546 and 1800 GeV in the range of four-momentum transfer squared 0.025<-t<0.29 GeV2. The data are well described by exponential form ebt with a slope b=15.28±0.58 (16.98±0.25) GeV−2 (1800) GeV. cross sections are, respectively, σel=12.87±0.30 19.70±0.85 mb.Received 5 August 1993DOI:https://doi.org/10.1103/PhysRevD.50.5518©1994 American Physical Society