0000000000126002

AUTHOR

Ll M. Mir

showing 3 related works from this author

Improved tau polarisation measurement

1996

Using 22 pb−1 of data collected at LEP in 1992 on the peak of the Z resonance, the ALEPH collaboration has measured the polarisation of the tau leptons decaying into $$ev\bar v, \mu v\bar v$$ ,πν, ρν and a1 ν from their individual decay product distributions. The measurement of the tau polarisation as a function of the production polar angle yields the two parametersN τ andN e, where, in terms of the axial and vector couplingsg Al andg Vl,N l=2g Vl gAl/(g Vl 2 +g 2 ). This analysis follows to a large extent the methods devised for the 1990 and 1991 data but with improvements which bring a better understanding of the systematic uncertainties. Combining the 1992 measurements with our previous…

Systematic errorPhysicsParticle physicsTime projection chamberPhysics and Astronomy (miscellaneous)010308 nuclear & particles physicsElectron–positron annihilationPhysicsWeinberg angle7. Clean energy01 natural sciencesParticle identificationNuclear physics0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Polar coordinate systemDecay product010306 general physicsParticle Physics - ExperimentLepton
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Tau leptonic branching ratios

1996

A sample of 62249 tau-pair events is selected from data taken with the ALEPH detector in 1991, 1992 and 1993. The measurement of the branching fractions for tau decays into electrons and muons is presented with emphasis on the study of systematic effects from selection, particle identification and decay classification. The results obtained are: B-e=17.79+/-0.12(stat)+/-0.06(syst)(%) and B-mu=17.31+/-0.11(stat)+/-0.05(syst)(%). Combined with the most recent ALEPH determination of the tau lifetime, these results provide a relative measurement of the leptonic couplings in the weak charged current for transverse W bosons: g(mu)/g(e)=1.0002+/-0.0051 and g(tau)/g(mu)=0.9943+/-0.0065. RI ANTONELLI…

PhysicsParticle physicsMuonPhysics and Astronomy (miscellaneous)[PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex]010308 nuclear & particles physicsElectron–positron annihilationPhysicsElectroweak interaction01 natural sciencesParticle identificationNuclear physicsPositron0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]High Energy Physics::Experiment010306 general physicsCharged currentParticle Physics - ExperimentBhabha scatteringBoson
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Search for the standard model Higgs boson

1993

Using a data sample corresponding to about 1 233 000 hadronic Z decays collected by the ALEPH experiment at LEP, the reaction e+e- --> HZ* has been used to search for the standard model Higgs boson, in association with missing energy when Z* --> nunuBAR, or with a pair of energetic leptons when Z* --> e+e- or mu+mu-. No signal was found and, at the 95% confidence level, m(H) exceeds 58.4 GeV/c2. RI ANTONELLI, ANTONELLA/C-6238-2011; Buttar, Craig/D-3706-2011; Stahl, Achim/E-8846-2011; Passalacqua, Luca/F-5127-2011; Murtas, Fabrizio/B-5729-2012; St.Denis, Richard/C-8997-2012; Forti, Francesco/H-3035-2011; Ferrante, Isidoro/F-1017-2012

Nuclear and High Energy PhysicsParticle physics[PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex]Electron–positron annihilationHadronElementary particle01 natural sciencesinternet searchingdistance calculationsStandard ModelALEPH Experiment0103 physical sciencesgraph applications.[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsALEPH experimentPhysicsMissing energy010308 nuclear & particles physicsPhysicsHigh Energy Physics::Phenomenologymetric spacelcsh:QC1-999Higgs bosonHigh Energy Physics::Experimentlcsh:PhysicsParticle Physics - ExperimentLepton
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