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Related papers: Event shape studies, \boldmath{$\alpha_s$} and its…

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We calculate the NNLO QED corrections to the $C$-even part of differential cross section of $e^+e^- \to \mu^+\mu^-$ process. We neglect power corrections in the electron mass and obtain the result in terms of Goncharov's polylogarithms.

High Energy Physics - Phenomenology · Physics 2025-05-15 Roman E. Gerasimov , Petr A. Krachkov , Roman N. Lee

Inclusive event shape variables have been measured in the Breit Frame for neutral current deep-inelastic positron-proton scattering using the H1 and ZEUS detectors at HERA. The variables thrust, jet broadening, C-parameter, jet mass and two…

High Energy Physics - Experiment · Physics 2007-05-23 G. J. McCance

The influence of nonvanishing quark masses on the total cross section in electron positron collisions and on the $Z$ decay rate is calculated. The corrections are expanded in $m^2/s$ and $\as$. Methods similar to those applied for the…

High Energy Physics - Phenomenology · Physics 2011-01-25 K. G. Chetyrkin , J. H. Kühn

Results are presented from a study of the structure of high energy hadronic events recorded by the L3 detector at sqrt(s)>192 GeV. The distributions of several event shape variables are compared to resummed O(alphaS^2) QCD calculations. We…

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

We point out that a study of event shapes at hadron colliders allows to explore novel aspects of QCD. These studies are today made easier by the development of a program which automates the resummation.

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Zanderighi

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

In the Standard Model the process e+e- -> gamma-gamma is fully described by QED. Measurements of the differential cross-sections from the four LEP experiments are compared to the QED expectation and limits are set on parameters describing…

High Energy Physics - Experiment · Physics 2017-08-23 K. Sachs

Electromagnetic (EM) probes such as photons and dileptons provide direct insight into the space-time evolution of the hot and dense matter formed in heavy-ion collisions. Being unaffected by strong interactions, they serve as penetrating…

Nuclear Experiment · Physics 2025-10-01 Sebastian Scheid

Hadronic event shape distributions are determined from data in e+e- collisions between 183 and 207 GeV. From these the strong coupling alpha_s is extracted in O(alpha_s^2), NLLA and matched O(alpha_s^2)+NLLA theory. Hadronisation…

High Energy Physics - Experiment · Physics 2014-11-17 The DELPHI Collaboration , J. Abdallah

Event shape data from e+e- annihilation into hadrons collected by the JADE experiment between sqrt(s)=14 and 44 GeV are used to determine the strong coupling alpha_S. QCD predictionscomplete to next-to-next-to-leading order (NLLO),…

High Energy Physics - Experiment · Physics 2009-06-01 S. Kluth

High intensity back-scattered laser beams will allow the efficient conversion of a substantial fraction of the incident lepton energy into high energy photons, thus significantly extending the physics capabilities of an electron-electron or…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky

Electron-positron annihilations at an average center-of-mass energy of 133 GeV from the four LEP-experiments are presented. This includes in particular the total cross-section and multiplicities, thrust, rapidity and transverse momentum…

High Energy Physics - Phenomenology · Physics 2007-05-23 Claus Grupen

We present precision results for distributions in global event shapes that can be measured at hadron colliders within experimental limitations. These predictions are obtained by combining exact next-to-leading order (NLO) with the all-order…

High Energy Physics - Phenomenology · Physics 2011-01-04 Andrea Banfi

The current status of theoretical work and experimental analyses on power corrections in QCD for e+e- annihilation will be reviewed. Measurements of the number of active quark flavours n_f and the QCD colour factors C_A and C_F derived from…

High Energy Physics - Experiment · Physics 2009-10-31 Stefan Kluth

This review describes the current status of precision QCD studies at the LHC. We introduce the main experimental and theoretical methods, discussing also their cross-stimulated developments and recent advances. The different types of QCD…

High Energy Physics - Phenomenology · Physics 2022-10-12 Thomas Gehrmann , Bogdan Malaescu

In this paper, we give comprehensive analyses for event shape observables in electron-positron annihilation by using the Principle of Maximum Conformality (PMC) which is a rigorous scale-setting method to eliminate the renormalization…

High Energy Physics - Phenomenology · Physics 2022-10-19 Sheng-Quan Wang , Chao-Qin Luo , Xing-Gang Wu , Jian-Ming Shen , Leonardo Di Giustino

The structure functions of real and virtual photons are derived from cross section measurements of the reaction e^+e^ -> e^+e^- + hadrons at LEP. The reaction is studied at \sqrt{s} ~ 91 GeV with the L3 detector. One of the final state…

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

The measurement of charged-particle event shape variables is presented in inclusive inelastic pp collisions at a center-of-mass energy of 7 TeV using the ATLAS detector at the LHC. The observables studied are the transverse thrust, thrust…

High Energy Physics - Experiment · Physics 2013-08-09 ATLAS Collaboration

The total and differential cross sections of the process e+e- -> n gamma with n >= 2 are measured using data collected by the L3 experiment at centre-of-mass energies of \sqrt{s}=183 and 189 GeV. The results are in agreement with the…

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

We introduce a set of correlations between energy flow and event shapes that are sensitive to the flow of color at short distances in jet events. These correlations are formulated for a general set of event shapes, which includes jet…

High Energy Physics - Phenomenology · Physics 2014-11-17 Carola F. Berger , Tibor Kucs , George Sterman