0000000000799551

AUTHOR

I. Cho

showing 4 related works from this author

Observation and Mass Measurement of the BaryonΞb−

2007

We report the observation and measurement of the mass of the bottom, strange baryon $\Xi^-_b$ through the decay chain $\Xi^-_b \to J/\psi \Xi^-$, where $J/\psi \to \mu^+ \mu^-$, $\Xi^- \to \Lambda \pi^-$, and $\Lambda \to p \pi^-$. Evidence for observation is based on a signal whose probability of arising from the estimated background is 6.6 x 10^{-15}, or 7.7 Gaussian standard deviations. The $\Xi^-_b$ mass is measured to be $5792.9\pm 2.5$ (stat.) $\pm 1.7$ (syst.) MeV/$c^2$.

Particle physicsPhysics MultidisciplinaryHadronGaussian distributionMass measurementGeneral Physics and Astronomyddc:500.2.Lambda baryon01 natural sciencesHigh Energy Physics - ExperimentXi baryonParticle decay0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Measurement theoryNuclear Experiment010306 general physicsProbabilityPhysicsMuon010308 nuclear & particles physicsPhysicsHyperonBackground fluctuationBaryonCrystallography14.20.Mr 13.30.Eg 13.60.RjHigh Energy Physics::ExperimentNucleonPhysical Review Letters
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Cross section measurements of high-p(T) dilepton final-state processes using a global fitting method

2008

We present a new method for studying high-$p_T$ dilepton events ($e^{\pm}e^{\mp}$, $\mu^{\pm}\mu^{\mp}$, $e^{\pm}\mu^{\mp}$) and simultaneously extracting the production cross sections of $p\bar{p} \to t\bar{t}$, $p\bar{p} \to W^+W^-$, and $p\bar{p} \to \ztt$ at a center-of-mass energy of $\sqrt{s} = 1.96$ TeV. We perform a likelihood fit to the dilepton data in a parameter space defined by the missing transverse energy and the number of jets in the event. Our results, which use $360 {\rm pb^{-1}}$ of data recorded with the CDF II detector at the Fermilab Tevatron Collider, are $\sigma(t\bar{t}) = 8.5_{-2.2}^{+2.7}$ pb, $\sigma(W^+W^-) = 16.3^{+5.2}_{-4.4}$ pb, and $\sigma(\ztt) =291^{+50}_…

PhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsPhysicsHigh Energy Physics::PhenomenologyGlobal fittingFOS: Physical sciencesddc:500.2State (functional analysis)Astronomy & Astrophysics;; Physics Particles & Fields01 natural sciences7. Clean energyHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)CrystallographyTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY0103 physical sciences_High Energy Physics::ExperimentProduction (computer science)010306 general physicsEnergy (signal processing)Bar (unit)Lepton
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First measurement of the W-boson mass in run II of the Tevatron.

2007

7 pages, 4 figures.-- PACS nrs.: 14.70.Fm; 13.38.Be; 13.85.Qk.-- ISI Article Identifier: 000250140600014.-- ArXiv pre-print available at: http://arxiv.org/abs/0707.0085.-- et al.

13.38.Be 14.70.Fm 12.15.Ji 13.85.QkParticle physicsSingle measurementPhysics MultidisciplinaryTevatronFOS: Physical sciencesGeneral Physics and AstronomyElementary particleData recordingddc:500.201 natural sciencesParticle detectorHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)[PACS] Decays of W bosons0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]W-boson massFermilabMeasurement theory010306 general physicsNuclear Experiment[PACS] Hadron-induced inclusive production with identified leptons photons or other nonhadronic particles (energy > 10 GeV)BosonsBosonPhysics010308 nuclear & particles physicsPhysicsHigh Energy Physics::PhenomenologyDetectorsTevatron[PACS] W bosonsHigh Energy Physics::ExperimentBar (unit)
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3C 279 Event Horizon Telescope imaging

2020

3C 279 is an archetypal blazar with a prominent radio jet that show broadband flux density variability across the entire electromagnetic spectrum. We use an ultra-high angular resolution technique - global Very Long Baseline Interferometry (VLBI) at 1.3mm (230GHz) - to resolve the innermost jet of 3C 279 in order to study its fine-scale morphology close to the jet base where highly variable gamma-ray emission is thought to originate, according to various models. The source was observed during four days in April 2017 with the Event Horizon Telescope (EHT) at 230 GHz, including the phased Atacama Large Millimeter/submillimeter Array (ALMA), at an angular resolution of ~20uarcsec (at a redshif…

observational astronomygalactic and extragalactic astronomyAstrophysics and AstronomyInterferometryAstrophysics::High Energy Astrophysical PhenomenaRadio galaxiesPhysicsGalaxiesNatural Sciences
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