Jet physics at LEP and world summary of #alpha#_s

Recent results on jet physics and tests of QCD from hadronic final states in e"+e"- annihilation at PETRA and at LEP are reviewed, with special emphasis on hadronic event shapes, charged particle production rates, properties of quark and gluon jets and determinations of #alpha#_s. The data in the entire energy range from PETRA to LEP-2 are in broad agreement with the QCD predictions. The world summary of measurements of #alpha#_s is updated and a detailed discussion of various methods to determine the overall error of #alpha#_s(M_Z0) is presented. The new world average is #alpha#_s(M_Z0)=0.119#+-#0.004. The size of the error depends on the treatment of correlated uncertainties. (orig.)Available from TIB Hannover: RN 6945(1998,43) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Quarks und Gluonen: 'farbige' Bausteine des Universums

An overview is given on the properties of quarks and gluons, on the state of theory and on current and future research activities in this area. Characterization of the fundamental particles (quarks, leptons) and of the strong and weak coupling strengthes is carried out in modern particle accelerators. By the Large Electron Positron Collider, LEP, (CERN, Geneva), electrons and positrons are accelerated in large storage rings (27 km perimeter) up to 55 GeV. One of the four LEP experiments, the Omni Purpose Detector At LEP, OPAL, is described in detail. Hadronic events analyzed at OPAL point to the existence of 'coloured' gluons predicted by quantum chromodynamics (QCD). In order to solve key questions of the basic theory (e.g. the search for Higgs bosons), the energy of LEP is raised to 95 GeV (LEP-II project), and in the year 2000, LEP-II is to be substituted by the Large Hadron Collider, LHC, with an energy up to 700 GeV. (WEN)SIGLEAvailable from TIB Hannover: RN 6945(1996,01) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Test des Standardmodells mit OPAL bei LEP Schlussbericht

SIGLEAvailable from TIB Hannover: DtF QN1(52,4) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Entwicklung von Detektorkomponenten fuer die Higgs- und Top-Suche am 16 TeV LHC beim CERN Schlussbericht

SIGLEAvailable from TIB Hannover: DtF QN1(52,1) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

QCD tests at e"+e"- colliders

A short review of the history and a 'slide-show' of QCD tests in e"+e"-annihilation is given. The world summary of measurements of #alpha#_s is updated. (orig.)Available from TIB Hannover: RN 6945(1997,37) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Experimental tests of asymptotic freedom

Measurements which probe the energy dependence of #alpha#_s, the coupling strength of the strong interaction, are reviewed. Jet counting in e"+e"-annihilation, combining results obtained in the centre of mass energy range from 22 to 133 GeV, provides direct evidence for an asymptotically free coupling, without the need to determine explicit values of #alpha#_s. Recent results from jet production in e p and in p p collisions, obtained in single experiments spanning large ranges of momentum transfer, Q"2, are in good agreement with the running of #alpha#_s as predicted by QCD. Mass spectra of hadronic decays of #tau#-leptons are analysed to probe the running #alpha#_s in the very low energy domain, 0.7 GeV"2 < Q"2 < M"2_#tau#. An update of the world summary of measurements of #alpha#_s(Q"2) consistently proves the energy dependence of #alpha#_s and results in a combined average of #alpha#_s(M_Z_"0=0.118#+-#0.006). (orig.)Available from TIB Hannover: RN 6945(1996,30) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Summary of #alpha#_s measurements

Measurements of the strong coupling strength #alpha#_s are reviewed and summarized. A number of new results presented at this conference confirm the evidence for a significant energy dependence of #alpha#_s, in agreement with the predictions of Quantum Chromodynamics, and may provide new insights into the pending problem of systematic differences between low- and high-energy measurements of #alpha#_s. Future developments which are necessary to increase the current precision of the world average of #alpha#_s(MZ"0) are discussed. (orig.)Available from TIB Hannover: RN 6945(1994,30) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Status of #alpha#_s measurements

The status of measurements of #alpha#_s is reviewed and the most recent results, as reported at this conference, are summarised. The new measurements are compatible with earlier results, such that the world average is still #alpha#_s(MsubZ"0)=0.117#+-#0.006. The relevant QCD equations whose 3"r"d order terms were misprinted in some of the previous reviews are corrected. (orig.)23 refs.Available from TIB Hannover: RN 69451995,14) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman