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Related papers: Final QCD results from LEP

200 papers

Deep-inelastic ep scattering data taken with the H1 detector at HERA and corresponding to an integrated luminosity of 106 pb^{-1} are used to study the differential distributions of event shape variables. These include thrust, jet…

High Energy Physics - Experiment · Physics 2012-08-27 H1 Collaboration

The time-evolution of jets in hadronic e+e- events at LEP is investigated in both position- and momentum-space, with emphasis on effects due to color flow and particle correlations. We address dynamical aspects of the four…

High Energy Physics - Phenomenology · Physics 2009-09-11 John Ellis , Klaus Geiger

Next-to-Leading-Order(NLO) QCD corrections to J/jpsi plus eta_c production in e+e- annihilation at sqrt{s}=10.6 GeV is calculated in this paper, and an analytic result is obtained. By choosing proper physical parameters, a K factor (ratio…

High Energy Physics - Phenomenology · Physics 2008-11-26 Bin Gong , Jian-Xiong Wang

The LHCb detector has demonstrated a proven competitiveness across a wide range of physics analyses thanks to its forward coverage. These proceedings describe: i) complementary measurements using heavy flavour jets, ii) Electroweak (EW)…

High Energy Physics - Experiment · Physics 2026-05-13 Emilio Xosé Rodríguez Fernández

Heavy flavour tagging provides a broad range of possibilities in testing QCD features at LEP. We present here a study of 4jets events at LEP I where the so-called light gluinos could be directly produced. We show that microvertex techniques…

High Energy Physics - Phenomenology · Physics 2011-09-13 S. Moretti , R. Munoz-Tapia , K. Odagiri

Hard QCD results in proton-proton collisions at sqrt(s) = 7 TeV with jets from data recorded up to the end of 2010 by the CMS and ATLAS experiments at the LHC are reported. Inclusive jet and di-jet cross section measurements as well as…

High Energy Physics - Experiment · Physics 2015-06-03 Sven Menke

Selected topics on precision tests of the Standard Model of the Electroweak and the Strong Interaction at the LEP $e^+e^-$ collider are presented, including an update of the world summary of measurements of $\alpha_s$, representing the…

High Energy Physics - Experiment · Physics 2007-05-23 S. Bethke

Determinations of the strong coupling constant alpha_S at centre-of-mass energies of 192 through 202 GeV at LEP are presented. The energy evolution of alpha_S is in agreement with the prediction of QCD. The combined investigation of OPAL…

High Energy Physics - Experiment · Physics 2016-08-31 O. Biebel

Jet and di-jet production are studied in collisions of quasi-real photons collected during the LEP2 program at e+e- center-of-mass energies from 189 to 209 GeV. OPAL reports good agreement of NLO perturbative QCD with the measured…

High Energy Physics - Experiment · Physics 2011-09-13 Thorsten Wengler

The activities of the QCD working group concentrated on improving the understanding and Monte Carlo simulation of multi-jet final states due to hard QCD processes at LEP, i.e. quark-antiquark plus multi-gluon and/or secondary quark…

An important issue in the direct reconstruction method of determining the $W$ mass from $q\bar q Q\bar Q$ events at LEP2 concerns the impact of the relatively unknown QCD interconnection effects. It has been suggested that a study of `short…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Ballestrero , V. A. Khoze , E. Maina , S. Moretti , W. J. Stirling

The combined results of the search for the Standard Model Higgs boson from the four LEP experiments are given. These results are based on the full data sample collected by ALEPH, DELPHI, L3 and OPAL at centre-of-mass energies up to 209GeV,…

High Energy Physics - Experiment · Physics 2007-05-23 F. Cerutti

Results are presented from a study of the structure of hadronic events in high-energy e+e- interactions detected by the L3 detector at LEP. Various event shape distributions and their moments are measured at several energy points at and…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

The top quark mass is one of the fundamental parameters of the Standard Model. In these proceedings, recent measurements of the top quark mass in $pp$ collisions at centre-of-mass energies of $\sqrt s=7$ and 8~TeV data in Run I of the Large…

High Energy Physics - Experiment · Physics 2019-08-13 Oleg Brandt

After a comment on the performance of LEP some highlights of the LEP1 and LEP2 physics programmes are reviewed. The talk concentrates on the precision measurements at the Z resonance, two fermion production above the Z, W+W- production, ZZ…

High Energy Physics - Experiment · Physics 2009-11-07 J. Drees

We directly fit the experimentally measured energy dependence of the average value of 1-Thrust, <1-T>, over the e^+e^- centre-of-mass energy range Q=14 - 172 GeV to the QCD expectation obtained by integrating up the evolution equation for…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. M. Campbell , E. W. N. Glover , C. J. Maxwell

We consider subleading power corrections to event shape variables in $e^+e^-$ collisions at the first order in the QCD coupling $\alpha_s$. We start from the jettiness variable $\tau_2$ and the $y_{23}$ resolution variable for the $k_T$ jet…

High Energy Physics - Phenomenology · Physics 2024-05-13 Luca Buonocore , Massimiliano Grazzini , Flavio Guadagni , Luca Rottoli

First LHC data have been collected and collisions at a center-of-mass energy of 7 TeV are anticipated for the next months. The commissioning of the detectors and the re-establishment of the Standard Model in the new energy regime will be…

High Energy Physics - Phenomenology · Physics 2010-02-22 Klaus Rabbertz

The study of the differences of the fragmentation of quarks and gluons to jets of hadrons gives insight into the fundamental structure of QCD. Results from different approaches to properties of quarks and gluons are shown. The colour factor…

High Energy Physics - Experiment · Physics 2007-05-23 Martin Siebel

QCD one-loop corrections to the full gauge invariant set of electroweak diagrams describing the hadronic process $e^+ e^- \to u~\bar d~s~\bar c$ are computed. Four-jet shape variables for $WW$ events are studied at next-to-leading order and…

High Energy Physics - Phenomenology · Physics 2011-02-01 E. Maina , R. Pittau , M. Pizzio