0000000000358815

AUTHOR

Stephen R. Leone

showing 3 related works from this author

Precision Measurement of theX(3872)Mass inJ/ψπ+π−Decays

2009

We present an analysis of the mass of the X(3872) reconstructed via its decay to J/psi pi(+)pi(-) using 2.4 fb(-1) of integrated luminosity from p (p) over bar collisions at root s = 1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. The possible existence of two nearby mass states is investigated. Within the limits of our experimental resolution the data are consistent with a single state, and having no evidence for two states we set upper limits on the mass difference between two hypothetical states for different assumed ratios of contributions to the observed peak. For equal contributions, the 95% confidence level upper limit on the mass difference is 3.6 MeV/c(2). Un…

PhysicsParticle physicsMeson010308 nuclear & particles physicsHadronTevatronGeneral Physics and AstronomyQuarkonium7. Clean energy01 natural sciencesLuminosityNuclear physicsParticle decayPion0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsX(3872)Physical Review Letters
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Measurement of Higgs boson production in the diphoton decay channel inppcollisions at center-of-mass energies of 7 and 8 TeV with the ATLAS detector

2014

A measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.3 fb(-1) at root s = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. The number of observed Higgs boson decays to diphotons divided by the corresponding Standard Model prediction, called the signal strength, is found to be mu = 1.17 +/- 0.27 at the value of the Higgs boson mass measured by ATLAS, m(H) = 125.4 GeV. The analysis is optimized to measure the signal strengths for individual Higgs boson production processes at this value of m(H). They are found to be mu(ggF) = 1.32…

PhysicsNuclear and High Energy PhysicsParticle physicsPhotonLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::Phenomenology7. Clean energy01 natural sciencesStandard ModelVector bosonGluonNuclear physicsmedicine.anatomical_structure13. Climate actionAtlas (anatomy)0103 physical sciencesHiggs bosonmedicineHigh Energy Physics::ExperimentCenter of mass010306 general physicsPhysical Review D
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Measurements of spin correlation in top-antitop quark events from proton-proton collisions ats=7  TeVusing the ATLAS detector

2014

Measurements of spin correlation in top quark pair production are presented using data collected with the ATLAS detector at the LHC with proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 4.6 fb(-1). Events are selected in final states with two charged leptons and at least two jets and in final states with one charged lepton and at least four jets. Four different observables sensitive to different properties of the top quark pair production mechanism are used to extract the correlation between the top and antitop quark spins. Some of these observables are measured for the first time. The measurements are in good agreement with the Stan…

QuarkPhysicsNuclear and High Energy PhysicsParticle physicsTop quarkLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyTevatron01 natural sciences7. Clean energyBottom quarkNuclear physicsPair production0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsLeptonBosonPhysical Review D
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