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Related papers: Review on alpha_s at LEP

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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

We consider a method for determining the QCD strong coupling constant using fits of perturbative predictions for event shape averages to data collected at the LEP, PETRA, PEP and TRISTAN colliders. To obtain highest accuracy predictions we…

High Energy Physics - Phenomenology · Physics 2021-04-13 Adam Kardos , Gábor Somogyi , Andrii Verbytskyi

We report results on measurements of the strong coupling \as from event shape data at \Petra and \Lep. These include analyses of their distributions employing the recent NLLO calculations and analyses of their moments using NLO and power…

High Energy Physics - Experiment · Physics 2008-10-21 Christoph Pahl

In this proceedings we discuss a prescription to extract the QCD strong coupling constant at $N^{3}LO$ precision in perturbative QCD using a combination of ${\cal{O}}(\alpha_{S}^{3})$ calculations in pQCD and estimations of the…

High Energy Physics - Phenomenology · Physics 2021-10-29 Adam Kardos , Gábor Somogyi , Andrii Verbytskyi

We report on several methodologically different NNLO determinations of the strong coupling constant from event shapes and related observables in e+e- annihilation. The event shape distributions are analyzed within a combined framework of…

High Energy Physics - Phenomenology · Physics 2010-11-19 Gionata Luisoni

Multi-hadronic events produced in e+e- collisions provide an excellent laboratory to study QCD, the theory of strong interactions, and in particular to determine the strong coupling parameter alpha_s and demonstrate its predicted behavior…

High Energy Physics - Experiment · Physics 2017-08-23 T. Wengler

A study of the energy dependence of event shape observables is presented. The strong coupling constant \alpha_s has been determined from the mean values of six event shape observables. Power corrections, employed for the measurement of…

High Energy Physics - Experiment · Physics 2009-10-30 O. Biebel

The measurement of the strong coupling alpha_S using hadronic event shape distributions measured with the OPAL detector at center-of-mass energies between 91 and 209 GeV is summarized. For this measurement hadronic event shape distributions…

High Energy Physics - Experiment · Physics 2011-05-25 Jochen Schieck

We present a determination of the strong coupling constant from a fit of QCD predictions for six event-shape variables, calculated at next-to-next-to-leading order (NNLO) and matched to resummation in the next-to-leading-logarithmic…

High Energy Physics - Phenomenology · Physics 2009-09-24 G. Dissertori , A. Gehrmann-De Ridder , T. Gehrmann , E. W. N. Glover , G. Heinrich , G. Luisoni , H. Stenzel

A summary is given of the current status of measurements of the strong coupling constant $\alpha_s$ performed at LEP. These include measurements from inclusive observables as well as from event shape variables. Recent results based on power…

High Energy Physics - Experiment · Physics 2007-05-23 G. Dissertori

New results from measurements of the strong coupling constant $\alpha_s(M_Z)$ at LEP are presented. In particular, a new LEP combination of results based on event-shape variables has become available, where a new method for the estimation…

High Energy Physics - Experiment · Physics 2009-11-07 G. Dissertori

The `XIIIth Quark Confinement and the Hadron Spectrum' conference (Confinement 2018) contained a `Round Table Discussion' on the status of the determinations of the strong coupling $\alpha_s(m_Z)$ as well as prospects for future…

High Energy Physics - Phenomenology · Physics 2018-12-17 Antonio Pich , Juan Rojo , Rainer Sommer , Antonio Vairo

The strong coupling alpha_s(M_Z^2) has been measured using hadronic decays of Z^0 bosons collected by the SLD experiment at SLAC. The data were compared with QCD predictions both at fixed order, O(alpha_s^2), and including resummed analytic…

High Energy Physics - Experiment · Physics 2008-11-26 K. Abe

The potential of the TESLA linear e+e- collider to determine the strong coupling constant, alpha_S, at 500 GeV is investigated. Experimental complications due to background from W- and Z-pairs, top-production, initial state photon radiation…

High Energy Physics - Experiment · Physics 2007-05-23 O. Biebel

The strong coupling alpha_s is a fundamental parameter of the Standard Model. In comparison to parameters like alpha_em and M_Z it is relatively poorly known. However the precision of alpha_s measurements has improved dramatically in recent…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. J. Stirling

The latest experimental and theoretical developments in the high-precision determination of the strong coupling $\alpha_s$ are briefly reviewed. Six groups of observables: (i) lattice QCD data, (ii) hadronic $\tau$ decays, (iii)…

High Energy Physics - Experiment · Physics 2018-06-19 David d'Enterria

We measure the strong coupling constant at NNLO corrections. We do this analysis with moments of event shape variables: thrust, C parameter, heavy jet mass, wide and total jet broadening, by fitting the L3 and DELPHI data with NNLO model.…

High Energy Physics - Phenomenology · Physics 2015-06-19 L. Khajooee , T. Kalalian , R. Saleh-Moghaddam , A. Sepehri , M. E. Zomorrodian

Recent results on measurements of the strong coupling $\alpha_S$ from LEP are reported. These include analyses of the 4-jet rate using the Durham or Cambridge algorithm, of hadronic $Z^0$ decays with hard final state photon radiation, of…

High Energy Physics - Experiment · Physics 2008-11-26 Stefan Kluth

In this contribution we explore one of the many possibilities of determining the strong coupling constant $\alpha_S$ at hadron colliders. The method considered is quite unique compared to other methods in that the value of $\alpha_S$ is…

High Energy Physics - Phenomenology · Physics 2009-10-30 Walter T. Giele

One of the most precise measurements of the strong coupling constant alpha_s(MZ) is obtained in the context of global analyses of precision electroweak data. This article reviews the sensitivity of different electroweak observables to…

High Energy Physics - Phenomenology · Physics 2009-11-11 H. Stenzel
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