0000000001031101

AUTHOR

Alberto Maria Messineo

showing 2 related works from this author

Measurement of the Michel parameters and the nu(tau) helicity in tau lepton decays

2001

A measurement of the Michel parameters and the average $\nu_\tau$ helicity in $\tau$ lepton decays is described. The data was collected with the ALEPH detector at LEP during the years 1991 to 1995. A total integrated luminosity of 155\,$\text{pb}^{-1}$ is analysed. The Michel parameters $\rho_l$, $\xi_l$, $(\xi\delta)_l$ ($l=e,\mu$), and $\eta_\mu$ are determined for the leptonic deca ys, and the chirality parameters $\xi_\pi$, $\xi_\rho$, and $\xi_{a_1}$ for the hadronic final states. Under the assumptions of $e$\bis $\mu$ universality and $\xi_\pi=\xi_\rho=\xi_{a_1}$, the values $\rho_l=0.742\pm 0.016, \eta_l=0.01 2\pm 0.026,\break (\xi\delta)_l=0.776\pm 0.051, \xi_l=0.986\pm 0.074$, and …

PhysicsParticle physics[PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex]Physics and Astronomy (miscellaneous)010308 nuclear & particles physicsElectron–positron annihilationHadronParity (physics)Weak interaction01 natural sciencesHelicity0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Michel parametersHigh Energy Physics::Experiment010306 general physicsEngineering (miscellaneous)Particle Physics - ExperimentLepton
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Search for Higgs bosons decaying to WW in e(+)e(-) stope collisions at LEP

2006

A search for Higgs bosons produced in association with a fermion pair, and decaying to WW, is performed with the data collected by the ALEPH detector at centre-of-mass energies ranging from 191 to 209 GeV. The data correspond to an integrated luminosity of 453.2 pb^-1. Thirteen exclusive selections are developed according to the different final state topologies. No statistically significant evidence for a Higgs boson decaying into a WW pair has been found. An upper limit is derived, as a function of the Higgs boson mass, on the product of the e+e- -> Hff cross section and the H -> WW branching ratio. The data on the search for H -> WW are combined with previously published ALEPH re…

Particle physicsAlephPhysics and Astronomy (miscellaneous)Electron–positron annihilationFOS: Physical sciences7. Clean energy01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsEngineering (miscellaneous)BosonPhysicsLuminosity (scattering theory)010308 nuclear & particles physicsBranching fractionHigh Energy Physics::PhenomenologyFermionFunction (mathematics)3. Good healthHiggs bosonHigh Energy Physics::ExperimentHiggs Boson Invariant Mass Higgs Boson Mass Time Projection Chamber Inant VariableParticle Physics - Experiment
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