Search results for "14.80.-j"

showing 3 items of 3 documents

Search for long-lived particles decaying into electron or photon pairs with the D0 detector

2008

In this Letter we report on a search for long-lived particles that decay into final states with two electrons or photons. Such long-lived particles arise in a variety of theoretical models, like hidden valleys and supersymmetry with gauge-mediated breaking. By precisely reconstructing the direction of the electromagnetic shower we are able to probe much longer lifetimes than previously explored. We see no evidence of the existence of such long-lived particles and interpret this search as a quasi model-independent limit on their production cross section, as well as a limit on a long-lived fourth generation quark.

QuarkPhysicsParticle physicsPhoton010308 nuclear & particles physicsFOS: Physical sciencesGeneral Physics and AstronomyElementary particleElectron01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsMassless particleHigh Energy Physics - Experiment (hep-ex)Particle decayPair production13.85.Qk13.85.Rm14.65.-q14.80.-j0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsLepton
researchProduct

Search for new particles in two-jet final states in 7 TeV proton-proton collisions with the ATLAS detector at the LHC

2010

19 páginas, 2 figuras, 1 tabla.-- et al.(ATLAS Collaboration).

ProtonAtlas detectorPhysics::Instrumentation and DetectorsPhysics beyond the Standard ModelGeneral Physics and AstronomyJet (particle physics)particle physic01 natural sciencesSettore FIS/04 - Fisica Nucleare e SubnucleareHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)12.60.Rcddc:550[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]13.87.CeQCPhysicsPACS numbers: 13.85.Rm 12.60.Rc 13.87.Ce 14.80.-jLarge Hadron ColliderLuminosity (scattering theory)Cross sectionAcceleradors de partículesSettore FIS/01 - Fisica Sperimentale14.80.-jATLASnumbers: 13.85.Rm3. Good healthDijetsmedicine.anatomical_structureComputingMethodologies_DOCUMENTANDTEXTPROCESSINGTWO-JETSLHCParticle Physics - ExperimentjetsFinal stateParticle physicsCiências Naturais::Ciências Físicas:Ciências Físicas [Ciências Naturais]FOS: Physical sciencesddc:500.2530Partícules (Física nuclear)Nuclear physicsCross section (physics)Excited QuarksAtlas (anatomy)0103 physical sciencesmedicine010306 general physicsIntegrated luminosityProton proton collisionsParton Distributions010308 nuclear & particles physicsATLAS detectorsHigh Energy Physics::PhenomenologyFísicaPARTON DISTRIBUTIONS HADRON COLLIDERS EXCITED QUARKS DIJETSHadron CollidersHeavy particlesLHC ; ATLAS ; Collisions ; 7 TeV ; Two jets ; ResonancesExperimental High Energy PhysicsNEW PARTICLESproton-proton collisionsHigh Energy Physics::Experimentcollider
researchProduct

Search for new particles decaying into dijets in proton-antiproton collisions at root s=1.96 TeV

2009

We present a search for new particles which produce narrow two-jet (dijet) resonances using proton-antiproton collision data corresponding to an integrated luminosity of 1.13 fb(-1) collected with the CDF II detector. The measured dijet mass spectrum is found to be consistent with next-to-leading-order perturbative QCD predictions, and no significant evidence of new particles is found. We set upper limits at the 95% confidence level on cross sections times the branching fraction for the production of new particles decaying into dijets with both jets having a rapidity magnitude vertical bar y vertical bar < 1. These limits are used to determine the mass exclusions for the excited quark, axig…

QuarkNuclear and High Energy PhysicsParticle physicsFOS: Physical sciencesddc:500.2114 Physical sciences7. Clean energy01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)Particle decay0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Rapidity010306 general physics13.85.Rm 14.70.Pw 14.80.-jQuantum chromodynamicsPhysicshep-ex010308 nuclear & particles physicsBranching fractionPhysicsHigh Energy Physics::PhenomenologyPerturbative QCD3. Good healthDiquarkAntiprotonHigh Energy Physics::Experiment
researchProduct