Related papers: Jet Physics at LEP and World Summary of $\alpha_s$
Studies of hadronic final states of $e^+e^-$ annihilations at LEP are reviewed. The topics included cover hadronic event shapes, measurements of $\alpha_s$, determinations of QCD colour factors and tests of the non-Abelian gauge structure…
Data recorded by the JADE experiment at the PETRA e^+e^- collider were used to measure the event shape observables thrust, heavy jet mass, wide and total jet broadening and the differential 2-jet rate in the Durham scheme. For the latter…
Recent results on QCD studies in e+e- annihilations at LEP are presented. Data recorded by the LEP experiments at centre-of-mass energies between 91.2 to 206 GeV are included. The main topic is the measurement of alpha_s from event-shape…
Studies of hadronic final states of $e^+e^-$ annihilations, observed at the Large Electron Positron Collider LEP at CERN, are reviewed. The topics included cover measurements of $\alpha_s$, hadronic event shapes and hadronisation studies,…
The high hadronic event statistics collected at the Z energy (LEP I) allowed a good understanding of the QCD dynamics. The coupling constant $\alpha_s$ has been measured with several methods giving a global average $\alpha_s(M_Z) = 0.122…
Recent results on the energy spectra in QCD jets are reported. Within the Modified Leading Logarithmic Approximation (MLLA) and the Local Parton Hadron Duality (LPHD) model one finds a very good description of the $e^+e^-$ data from the…
Experimental results on jet physics at LEP and SLC are reviewed and compared with perturbative QCD predictions. The discussion includes determinations of the strong coupling $\as$, measurements of event shape distributions and jet cross…
In quark-antiquark pair production at LEP, many features of the hadronic final state can be predicted by QCD. Using data collected by the OPAL experiment, we present the statistical distributions of fourteen "event shape observables," which…
Results from the study of jets in hadronic final states produced in e+e- annihilation at sqrt(s)=14 to 209 GeV are discussed. Precise measurements of the strong coupling alpha_S at many points of sqrt(s) provide convincing evidence for the…
A summary of some recent studies in jet physics is given. Topics include leading particle production in light flavor events in e+e- annihilations, an analytical treatment of gluon and quark jets at the next-to-next-to-next-to-leading order…
Hadronic events produced in e+e- collisions by the LEP collider and recorded by the OPAL detector were used to form distributions based on the number of reconstructed jets. The data were collected between 1995 and 2000 and correspond to…
The QCD coupling $\alpha_s$ is extracted from the energy evolution of the first two moments (multiplicity and mean) of the parton-to-hadron fragmentation functions at low fractional hadron momentum $z$. Comparisons of the experimental…
A complete numerical solution of the evolution equation for parton multiplicities in quark and gluon jets with initial conditions at threshold is presented. Data on both hadron and jet multiplicities in e+e- annihilation are well described…
Measurements of $\alpha_s$, the coupling strength of the Strong Interaction between quarks and gluons, are summarised and an updated value of the world average of $\alpha_s (M_Z)$ is derived. Building up on previous reviews, special…
Several preliminary QCD results from e+e- interactions at LEP are reported. These include studies of event shape variables, which are used to determine alpha_s and for studies of the validity of power corrections. Further, a study of color…
We review the current status of analyses of multijet final states in e+e- annihilation. Results for jet observables from LEP 1, LEP 2 and from the reanalysis of the PETRA experiment JADE will be presented. A determination of the b-quark…
Re-analysed JADE data were used to determine alpha_S at sqrt{s} = 14-44 GeV on the basis of resummed calculations for event shapes and hadronisation models tuned to LEP data. The combined result is alpha_S(M_Z) = 0.1194 +/- 0.0082/0.0068…
A study of perturbative QCD calculations combined with power corrections to model hadronisation effects is presented. The QCD predictions are fitted to differential distributions and mean values of event shape observables measured in e+e-…
We discuss systematically the consistency of light gluinos with data on perturbative QCD from deep inelastic scattering, quarkonia, jets at LEP, and the total hadronic cross-section in ${e^+ e^-}$ annihilation on the $Z$ peak and elsewhere.…
We improve previously derived analytical estimates of hadronisation corrections to QCD jets at hadron colliders, firmly establishing at the two-loop level the link to the well-known power corrections to LEP event-shape variables. The…