Search results for "Z0"

showing 10 items of 712 documents

PRODUCTION-RATE AND DECAY LIFETIME MEASUREMENTS OF B(S)0 MESONS AT LEP USING D(S) AND PHI MESONS

1994

The study of the properties of inclusive production of Ds mesons and of events in which a φ{symbol} and a muon are present in the same jet provides two independent measurements of the probability, fs w, for a heavy quark to hadronize into a strange B or D meson. The data sample analysed corresponds to 243,000 hadronic Z0 decays. The combined value of these measurements is fs w=0.19±0.06±0.08. From the flight distance distributions of Ds and of (φ{symbol}-lepton) secondary vertices, with the lepton emitted at high transverse momentum relative to the jet axis, two values are obtained for the Bs 0 meson lifetime. Combining these measurements with a previous result based on the study of Ds-μ ev…

QuarkParticle physicsPhysics and Astronomy (miscellaneous)MesonLUND MONTE-CARLOElectron–positron annihilationNuclear TheoryJet (particle physics)01 natural sciencesJET FRAGMENTATIONNuclear physicsPHYSICS0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]B mesonZ0010306 general physicsNuclear ExperimentEngineering (miscellaneous)PhysicsMuonB-MESONS010308 nuclear & particles physicsPhysicsHigh Energy Physics::PhenomenologyLUND MONTE-CARLO; JET FRAGMENTATION; B-MESONS; PHYSICS; Z0High Energy Physics::ExperimentFísica nuclearParticle Physics - ExperimentProduction rateLepton
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Consistent measurements of alpha(s) from precise oriented event shape distributions

2000

An updated analysis using about 1.5 million events recorded at $\sqrt{s} = M_Z$ with the DELPHI detector in 1994 is presented. Eighteen infrared and collinear safe event shape observables are measured as a function of the polar angle of the thrust axis. The data are compared to theoretical calculations in ${\cal O} (\alpha_s^2)$ including the event orientation. A combined fit of $\alpha_s$ and of the renormalization scale $x_{\mu}$ in $\cal O(\alpha_s^2$) yields an excellent description of the high statistics data. The weighted average from 18 observables including quark mass effects and correlations is $\alpha_s(M_Z^2) = 0.1174 \pm 0.0026$. The final result, derived from the jet cone energ…

QuarkParticle physicsPhysics and Astronomy (miscellaneous)OPTIMIZED PERTURBATION-THEORY; JET CROSS-SECTIONS; E+ E ANNIHILATION; QUANTUM CHROMODYNAMICS; E(+)E(-) ANNIHILATION; QCD CALCULATIONS; Z0 RESONANCE; MONTE-CARLO; DECAYS; ALPHA(S)(M(Z)(2))QCD CALCULATIONSFOS: Physical sciencesScale (descriptive set theory)01 natural sciences7. Clean energyDECAYSPartícules (Física nuclear)High Energy Physics - ExperimentRenormalizationHigh Energy Physics - Experiment (hep-ex)MONTE-CARLO0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Engineering (miscellaneous); Physics and Astronomy (miscellaneous)010306 general physicsEngineering (miscellaneous)ALPHA(S)(M(Z)(2))DELPHIPhysicsQUANTUM CHROMODYNAMICS010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyOrder (ring theory)ObservableFunction (mathematics)E(+)E(-) ANNIHILATIONLARGE ELECTRON POSITRON COLLIDEROrientation (vector space)Experimental uncertainty analysisOPTIMIZED PERTURBATION-THEORYPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSJET CROSS-SECTIONSFísica nuclearHigh Energy Physics::ExperimentE+ E ANNIHILATIONZ0 RESONANCEParticle Physics - Experiment
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Search for composite and exotic fermions at LEP 2

1999

A search for unstable heavy fermions with the DELPHI detector at LEP is reported. Sequential and non-canonical leptons, as well as excited leptons and quarks, are considered. The data analysed correspond to an integrated luminosity of about 48~pb$^{-1}$ at an $e^+e^-$ centre-of-mass energy of 183~GeV and about 20~pb$^{-1}$ equally shared between the centre-of-mass energies of 172~GeV and 161~GeV. The search for pair-produced new leptons establishes 95\% confidence level mass limits in the region between 70~GeV/$c^2$ and 90~GeV/$c^2$, depending on the channel. The search for singly produced excited leptons and quarks establishes upper limits on the ratio of the coupling of the excited fermio…

QuarkParticle physicsPhysics and Astronomy (miscellaneous)PAIR PRODUCTIONCHARGED HEAVY-LEPTONSFOS: Physical sciences7. Clean energy01 natural sciencesPartícules (Física nuclear)CROSS-SECTIONSHigh Energy Physics - ExperimentE(+)E(-) COLLISIONSBHABHA SCATTERINGHigh Energy Physics - Experiment (hep-ex)0103 physical sciencesMONTE-CARLO PROGRAM[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONS010306 general physicsNuclear ExperimentEngineering (miscellaneous)PhysicsLuminosity (scattering theory)010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyFermionCoupling (probability)Z0 DECAYSExcited stateHigh Energy Physics::ExperimentFísica nuclearROOT-S=161 GEVEXCITED LEPTONSCHARGED HEAVY-LEPTONS; MONTE-CARLO PROGRAM; EXCITED LEPTONS; E(+)E(-) COLLISIONS; Z0 DECAYS; ROOT-S=161 GEV; RADIATIVE-CORRECTIONS; BHABHA SCATTERING; PAIR PRODUCTION; CROSS-SECTIONSParticle Physics - ExperimentLepton
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"Table 1" of "Study of $W$ boson production in association with beauty and charm"

2016

Summary of the results. All results are reported within a fiducial region that requires a jet with $p_\rm{T} > 20$ GeV in the pseudorapidity range $2.2 < \eta < 4.2$, a muon with $p_\rm{T} > 20$ GeV in the pseudorapidity range $2.0 < \eta < 4.5$, $p_\rm{T}(\mu+j) > 20$ GeV, and $\Delta R(\mu, j) > 0.5$. For $Z+$jet events both muons must fulfill the muon requirements and $60 < M(\mu\mu) < 120$ GeV; the $Z+$jet fiducial region does not require $p_\rm{T}(\mu+j) > 20$ GeV.

SIG/SIG7000.0-8000.0Z ProductionP P --> W- CJET XIntegrated Cross SectionP P --> W+ CJET XJet ProductionCross SectionP P --> W- BJET XInclusiveBeautyP P --> Z0 JET XProton-Proton ScatteringP P --> W+ BJET XAsymmetry MeasurementP P --> W+ JET XP P --> W- JET XBottomW ProductionASYM
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"Table 2" of "A measurement of the ratio of the W and Z cross sections with exactly one associated jet in pp collisions at sqrt(s) = 7 TeV with ATLAS"

2013

The ratios of W to Z production in the fiducial region for the individual lepton channels and for the channels combined.

SIG/SIGZ ProductionHigh Energy Physics::PhenomenologyIntegrated Cross Section7000.0Astrophysics::Cosmology and Extragalactic AstrophysicsJet ProductionCross SectionInclusiveP P --> Z0 JET XProton-Proton ScatteringP P --> W+ JET XHigh Energy Physics::ExperimentP P --> W- JET XW ProductionComputer Science::Information Theory
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"Table 14" of "Measurement of the production cross section for Z/gamma* in association with jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS d…

2014

Ratio of cross sections for N/N-1 inclusive jet multiplicities for the electron channel and the muon channel in the individual lepton fiducial regions and uncorrected for QED effects.

SIG/SIGZ ProductionHigh Energy Physics::PhenomenologyIntegrated Cross SectionAstrophysics::Instrumentation and Methods for AstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsJet ProductionCross SectionInclusiveP P --> Z0 JET XP P --> GAMMA* JET XProton-Proton ScatteringHigh Energy Physics::ExperimentComputer Science::Information Theory
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"Table 1" of "Determination of sin**2 theta(w)(eff) using jet charge measurements in hadronic Z decays"

1996

The first sytematic error is due to the experimental uncertainties, whilst the second is due to the uncertainties in the quark charge separations.

SIN2TWHigh Energy Physics::LatticeE+ E- --> HADRONSE+ E- --> Z0E+ E- ScatteringHigh Energy Physics::PhenomenologyExclusiveHigh Energy Physics::Experiment91.2
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"Table 26" of "Measurements of the line shape of the Z0 and determination of electroweak parameters from its hadronic and leptonic decays"

1994

The systematic error shown for SIN2TW is due to the uncertainty in the Higgs mass.

SIN2TWHigh Energy Physics::LatticeE+ E- --> Z0E+ E- ScatteringHigh Energy Physics::PhenomenologyGAExclusiveHigh Energy Physics::ExperimentE+ E- --> LEPTON+ LEPTON-91.2GV
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"Table 1" of "The Forward - backward asymmetry for charm quarks at the Z pole"

1995

Value of SIN2TW(eff) from CQ-quark asymmetries.

SIN2TWHigh Energy Physics::LatticeE+ E- --> Z0Nuclear TheoryHigh Energy Physics::PhenomenologyE+ E- --> CQBAR CQE+ E- --> D*(2010)- X91.2E+ E- --> D*(2010)+ XInclusiveAsymmetry MeasurementCharm productionE+ E- ScatteringAstrophysics::Solar and Stellar AstrophysicsExclusiveHigh Energy Physics::ExperimentASYM
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"Table 8" of "Measurement of electroweak parameters from Z decays into Fermion pairs"

1990

No description provided.

SINTW88.227E+ E- --> Z0E+ E- ScatteringGAALPHASExclusiveE+ E- --> LEPTON+ LEPTON-GV
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