0000000001049385

AUTHOR

Thorsten Chwalek

showing 36 related works from this author

Search for a Standard Model Higgs Boson inWH→ℓvbb¯inpp¯Collisions ats=1.96  TeV

2009

We present a search for a standard model Higgs boson produced in association with a W boson using 2.7 fb(-1) of integrated luminosity of pp collision data taken at square root s = 1.96 TeV. Limits on the Higgs boson production rate are obtained for masses between 100 and 150 GeV/c(2). Through the use of multivariate techniques, the analysis achieves an observed (expected) 95% confidence level upper limit of 5.6 (4.8) times the theoretically expected production cross section for a standard model Higgs boson with a mass of 115 GeV/c(2).

PhysicsParticle physicsLuminosity (scattering theory)010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyGeneral Physics and AstronomyElementary particle01 natural sciencesStandard ModelNuclear physics0103 physical sciencesHiggs bosonGrand Unified TheoryHigh Energy Physics::ExperimentLimit (mathematics)Quantum field theory010306 general physicsBosonPhysical Review Letters
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Combined Tevatron upper limit ongg→H→W+W−and constraints on the Higgs boson mass in fourth-generation fermion models

2010

We combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg -> H -> W+W- in p (p) over bar collisions at the Fermilab Tevatron Collider at root s = 1.96 TeV. With 4.8 fb(-1) of integrated luminosity analyzed at CDF and 5.4 fb(-1) at D0, the 95% confidence level upper limit on sigma(gg -> H) x B(H -> W+W-) is 1.75 pb at m(H) = 120 GeV, 0.38 pb at m(H) = 165 GeV, and 0.83 pb at m(H) = 200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% confidence level a standard-model-like Higgs boson with a mass between 131 and 204 GeV.

PhysicsNuclear and High Energy PhysicsParticle physicsGauge boson010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaHigh Energy Physics::PhenomenologyTevatronElementary particleFermion01 natural sciences7. Clean energyStandard ModelNuclear physics0103 physical sciencesHiggs bosonHigh Energy Physics::ExperimentFermilab010306 general physicsBosonPhysical Review D
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Search for Pair Production of Supersymmetric Top Quarks in Dilepton Events frompp¯Collisions ats=1.96  TeV

2010

We present the results of a search for pair production of the supersymmetric partner of the top quark (the top squark (t) over tilde (1)) decaying to a b quark and a chargino (chi) over tilde (+/-)(1) with a subsequent (chi) over tilde (+/-)(1) decay into a neutralino (chi) over tilde (0)(1), lepton l, and neutrino nu Using a data sample corresponding to 2.7 fb(-1) of integrated luminosity of p (p) over bar collisions at root s = 1: 96 TeV collected by the CDF II detector, we reconstruct the mass of top squark candidate events and fit the observed mass spectrum to a combination of standard model processes and (t) over tilde (1)(t) over tilde (1). We find no evidence for (t) over tilde (1)(t…

QuarkPhysicsTop quarkParticle physics010308 nuclear & particles physicsBranching fractionHigh Energy Physics::PhenomenologyGeneral Physics and Astronomy01 natural sciencesBottom quarkStandard ModelNuclear physicsCharginoPair production0103 physical sciencesNeutralinoHigh Energy Physics::ExperimentComputer Science::Data Structures and Algorithms010306 general physicsPhysical Review Letters
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Direct Measurement of theWProduction Charge Asymmetry inpp¯Collisions ats=1.96  TeV

2009

We wish to thank R.S. Thorne and W.J. Stirling for useful discussions on the theoretical predictions.We thank the Fermilab staff and the technical staffs of the participating institutions for their vital contributions. This work was supported by the U.S. Department of Energy and National Science Foundation; the Italian Istituto Nazionale di Fisica Nucleare; the Ministry of Education, Culture, Sports, Science and Technology of Japan; the Natural Sciences and Engineering Research Council of Canada; the National Science Council of the Republic of China; the Swiss National Science Foundation; the A.P. Sloan Foundation; the Bundesministerium fur Bildung und Forschung, Germany; the Korean Science…

European community010308 nuclear & particles physicsScience and engineeringGeneral Physics and AstronomyLibrary scienceCharge (warfare)7. Clean energy01 natural sciencesBildungBasic researchPolitical science0103 physical sciencesChristian ministry010306 general physicsEngineering researchChinaPhysical Review Letters
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Production ofψ(2S)mesons inpp¯collisions at 1.96 TeV

2009

We have measured the differential cross section for the inclusive production of $\ensuremath{\psi}(2\mathrm{S})$ mesons decaying to ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ that were produced in prompt or $B$-decay processes from $p\overline{p}$ collisions at 1.96 TeV. These measurements have been made using a data set from an integrated luminosity of $1.1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected by the CDF II detector at Fermilab. For events with transverse momentum ${p}_{T}(\ensuremath{\psi}(2\mathrm{S}))g2\text{ }\text{ }\mathrm{GeV}/c$ and rapidity $|y(\ensuremath{\psi}(2\mathrm{S}))|l0.6$ we measure the integrated inclusive cross section $\ensuremath…

Scattering cross-sectionPhysicsNuclear and High Energy PhysicsParticle physicsMeson010308 nuclear & particles physics0103 physical sciencesTransverse momentumHigh Energy Physics::ExperimentProduction (computer science)Rapidity010306 general physics01 natural sciencesPhysical Review D
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Study of the associated production of photons andb-quark jets inpp¯collisions ats=1.96  TeV

2010

The cross section for photon production in association with at least one jet containing a b quark has been measured in proton antiproton collisions at {radical}(s)=1.96 TeV. The data sample used corresponds to an integrated luminosity of 340 pb{sup -1} collected with the CDF II detector. Both the differential cross section as a function of photon transverse energy E{sub T}{sup {gamma}}and the total cross section are measured and compared to a next-to-leading order prediction for the process.

PhysicsNuclear and High Energy PhysicsParticle physicsLuminosity (scattering theory)Proton010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaOrder (ring theory)Elementary particleJet (particle physics)01 natural sciencesBottom quarkNuclear physicsAntiproton0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsEnergy (signal processing)Physical Review D
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Search for single top quark production inpp¯collisions ats=1.96  TeVin the missing transverse energy plus jets topology

2010

We report a search for single top quark production with the CDF II detector using 2.1 fb{sup -1} of integrated luminosity of pp collisions at {radical}(s)=1.96 TeV. The data selected consist of events characterized by large energy imbalance in the transverse plane and hadronic jets, and no identified electrons and muons, so the sample is enriched in W{yields}{tau}{nu} decays. In order to suppress backgrounds, additional kinematic and topological requirements are imposed through a neural network, and at least one of the jets must be identified as a b quark jet. We measure an excess of signal-like events in agreement with the standard model prediction, but inconsistent with a model without si…

PhysicsQuarkNuclear and High Energy PhysicsTop quarkParticle physics010308 nuclear & particles physicsHadronOrder (ring theory)Topology01 natural sciencesBottom quarkStandard ModelNuclear physics0103 physical sciencesGrand Unified TheoryHigh Energy Physics::ExperimentProduction (computer science)010306 general physicsPhysical Review D
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Measurement of theb-hadron production cross section using decays toμ−D0Xfinal states inpp¯collisions ats=1.96  TeV

2009

We report a measurement of the production cross section for b hadrons in p{bar p} collisions at {radical}s = 1.96 TeV. Using a data sample derived from an integrated luminosity 83 pb{sup -1} collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron, we analyze b hadrons, H{sub b}, partially reconstructed in the semileptonic decay mode H{sub b} {yields} {mu}{sup -} D{sup 0} X. Our measurement of the inclusive production cross section for b hadrons with transverse momentum p{sub T} > 9 GeV/c and rapidity |y| < 0.6 is {sigma} = 1.30 {micro}b {+-} 0.05 {micro}b(stat) {+-} 0.14 {micro}b(syst) {+-} 0.07 {micro}b({Beta}), where the uncertainties are statistical, systematic, a…

Semileptonic decayPhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsBranching fractionHadronTevatronSigma01 natural sciences7. Clean energyNuclear physics0103 physical sciencesTransverse momentumHigh Energy Physics::ExperimentRapidityFermilab010306 general physicsPhysical Review D
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Search forR-Parity Violating Decays of Sneutrinos toeμ,μτ, andeτPairs inpp¯Collisions ats=1.96  TeV

2010

7 paginas, 2 figuras, 3 tablas.-- PACS numbers: 14.80.Ly, 12.60.Jv, 13.85.Qk, 14.60.St.--CDF Collaboration: et al.

PhysicsParticle physics010308 nuclear & particles physicsQuark modelGeneral Physics and AstronomyElementary particle01 natural sciencesStandard ModelNuclear physicsParticle decayR-parity0103 physical sciencesGrand Unified TheoryNeutrino010306 general physicsLeptonPhysical Review Letters
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Combination of Tevatron searches for the standard model Higgs boson in the W+W- decay mode.

2010

11 páginas, 4 figuras, 1 tabla.-- CDF Collaboration: et al.

Particle physicsAstrophysics::High Energy Astrophysical PhenomenaTevatronFOS: Physical sciencesGeneral Physics and AstronomyElementary particleddc:500.2.PARTON DISTRIBUTIONS; HADRON COLLIDERS; QCD; NNLO7. Clean energy01 natural sciences114 Physical sciencesHigh Energy Physics - ExperimentStandard ModelNuclear physicsHigh Energy Physics - Experiment (hep-ex)Particle decay0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Grand Unified TheoryHADRON COLLIDERSFermilabTEVATRONNuclear Experiment010306 general physicsBosonPhysicsHIGGS BOSON010308 nuclear & particles physicsPhysicsHigh Energy Physics::PhenomenologyQCD3. Good healthPARTON DISTRIBUTIONSHiggs bosonCDFPhysics::Accelerator PhysicsHigh Energy Physics::ExperimentNNLOAnti-p p: interaction | Higgs particle: search for | gluon gluon: fusion | intermediate boson: fusion | quark antiquark: annihilation | Higgs particle: decay | Higgs particle --> W+ W- | W: pair production | W: leptonic decay | dilepton: final state | jet: multiplicity | cross section: upper limit | mass dependence | Higgs particle: mass | background | DZERO | CDF | Batavia TEVATRON Coll | anti-p p --> Higgs particle anything | anti-p p --> Higgs particle anything intermediate boson anything | anti-p p --> Higgs particle anything quark antiquark anything | 1960 GeV-cmsPhysical review letters
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Measurement of theWW+WZProduction Cross Section Using thelepton+jetsFinal State at CDF II

2010

We report two complementary measurements of the diboson (WW + WZ) cross section in the final state consisting of an electron or muon, missing transverse energy, and jets, performed using p{bar p} collision data at {radical}s = 1.96 TeV collected by the Collider Detector at Fermilab. The first method uses the dijet invariant mass distribution while the second method uses more of the kinematic information in the event through matrix-element calculations of the signal and background processes and has a higher sensitivity. The result from the second method has a signal significance of 5.4{sigma} and is the first observation of WW + WZ production using this signature. Combining the results from …

PhysicsParticle physicsMuon010308 nuclear & particles physicsGeneral Physics and AstronomyElementary particle01 natural sciences7. Clean energyStandard ModelNuclear physics0103 physical sciencesHigh Energy Physics::ExperimentProduction (computer science)Invariant mass010306 general physicsCollider Detector at FermilabEnergy (signal processing)LeptonPhysical Review Letters
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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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First measurement of the ratio of branching fractionsB(Λb0→Λc+μ−ν¯μ)/B(Λb0→Λc+π−)

2009

This article presents the first measurement of the ratio of branching fractions B(Lambda(0)(b) -> Lambda(+)(c) mu(-) (nu) over bar (mu))/B(Lambda(0)(b) -> Lambda(+)(c) pi(-)). Measurements in two control samples using the same technique B((B) over bar (0) -> D+ mu(-) (nu) over bar (mu))/B((B) over bar (0) -> D+ pi(-)) and B((B) over bar (0) -> D*(2010)(+) mu(-) (nu) over bar (mu))/B((B) over bar (0) -> D*(2010)(+) pi(-)) are also reported. The analysis uses data from an integrated luminosity of approximately 172 pb(-1) of p (p) over bar collisions at root s = 1: 96 TeV, collected with the CDF II detector at the Fermilab Tevatron. The relative branching fractions are measured to be B(Lambda(…

PhysicsSemileptonic decayNuclear and High Energy PhysicsMuonMeson010308 nuclear & particles physicsBranching fractionHigh Energy Physics::PhenomenologyAnalytical chemistryParticle Data GroupLambda01 natural sciences0103 physical sciencesHigh Energy Physics::ExperimentB meson010306 general physicsBar (unit)Physical Review D
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Search for a Fermiophobic Higgs Boson Decaying into Diphotons inpp¯Collisions ats=1.96  TeV

2009

A search for a narrow diphoton mass resonance is presented based on data from 3.0 fb{sup -1} of integrated luminosity from p{bar p} collisions at {radical}s = 1.96 TeV collected by the CDF experiment. No evidence of a resonance in the diphoton mass spectrum is observed, and upper limits are set on the cross section times branching fraction of the resonant state as a function of Higgs boson mass. The resulting limits exclude Higgs bosons with masses below 106 GeV/c{sup 2} at a 95% Bayesian credibility level (C.L.) for one fermiophobic benchmark model.

PhysicsParticle physicsMeson010308 nuclear & particles physicsBranching fractionHigh Energy Physics::PhenomenologyTevatronGeneral Physics and AstronomyElementary particle01 natural sciencesStandard ModelNuclear physics0103 physical sciencesMass spectrumHiggs bosonHigh Energy Physics::Experiment010306 general physicsBosonPhysical Review Letters
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Search for the DecaysB(s)0→e+μ−andB(s)0→e+e−in CDF Run II

2009

We report results from a search for the lepton flavor violating decays $B^0_{(s)}\to e^+\mu^-$, and the flavor-changing neutral-current decays $B^0_{(s)} \to e^+ e^-$. The analysis uses data corresponding to ${\rm 2 fb^{-1}}$ of integrated luminosity of $p \bar{p}$ collisions at $\sqrt{s}=1.96 {\rm TeV}$ collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron. The observed number of $B^0_{(s)}$ candidates is consistent with background expectations. The resulting Bayesian upper limits on the branching ratios at 90% credibility level are $\mathcal{B}(B^0_s \to e^{+}\mu^{-}) 47.8 {\rm TeV/c^2}$, and ${M_{LQ}}(B^0\to e^+ \mu^-) > 59.3 {\rm TeV/c^2}$, at 90% credibility l…

PhysicsParticle physicsLuminosity (scattering theory)010308 nuclear & particles physicsBranching fractionHigh Energy Physics::PhenomenologyTevatronGeneral Physics and Astronomy01 natural scienceslaw.inventionNuclear physicslaw0103 physical sciencesPhysics::Accelerator PhysicsHigh Energy Physics::ExperimentFermilab010306 general physicsColliderLeptonPhysical Review Letters
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Measurement of the top quark mass in the dilepton channel using mT2 at CDF

2010

We present measurements of the top quark mass using mT2, a variable related to the transverse mass in events with two missing particles. We use the template method applied to tt̅ dilepton events produced in pp̅ collisions at Fermilab’s Tevatron Collider and collected by the CDF detector. From a data sample corresponding to an integrated luminosity of 3.4  fb-1, we select 236 tt̅ candidate events. Using the mT2 distribution, we measure the top quark mass to be Mtop=168.0-4.0+4.8(stat)±2.9(syst)  GeV/c2. By combining mT2 with the reconstructed top quark mass distributions based on a neutrino weighting method, we measure Mtop=169.3±2.7(stat)±3.2(syst)  GeV/c2. This is the first application of …

PhysicsQuarkNuclear and High Energy PhysicsTop quarkParticle physicsMass distribution010308 nuclear & particles physicshep-exHadronHigh Energy Physics::PhenomenologyTevatronddc:500.201 natural sciences114 Physical scienceslaw.inventionNuclear physicslaw0103 physical sciencesTransverse massHigh Energy Physics::ExperimentFermilab010306 general physicsColliderNuclear Experiment
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Inclusive Search for Squark and Gluino Production inpp¯Collisions ats=1.96  TeV

2009

We report on a search for inclusive production of squarks and gluinos in p{bar p} collisions at {radical}s = 1.96 TeV, in events with large missing transverse energy and multiple jets of hadrons in the final state. The study uses a CDF Run II data sample corresponding to 2 fb-1 of integrated luminosity. The data are in good agreement with the standard model predictions, giving no evidence for any squark or gluino component. In an R-parity conserving minimal supergravity scenario with A{sub 0} = 0, mu < 0 and tan beta = 5, 95% C.L. upper limits on the production cross sections in the range between 0.1 pb and 1 pb are obtained, depending on the squark and gluino masses considered. For gluino …

PhysicsParticle physicsGluinoLuminosity (scattering theory)010308 nuclear & particles physicsSupergravityHadronGeneral Physics and AstronomySupersymmetry01 natural sciencesEngineering physicsStandard Modellaw.inventionArbitrarily largelaw0103 physical sciences010306 general physicsColliderPhysical Review Letters
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Measurements of branching fraction ratios andCPasymmetries inB±→DCPK±decays in hadron collisions

2010

9 paginas, 3 figuras, 2 tablas.-- PACS numbers: 13.25.Hw, 11.30.Er, 14.40.Nd.--CDF Collaboration: et al.

PhysicsNuclear and High Energy PhysicsParticle physicsMeson010308 nuclear & particles physicsBranching fractionQuark modelHadronElementary particle01 natural sciences3. Good healthNuclear physicsParticle decayPion0103 physical sciencesB meson010306 general physicsPhysical Review D
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Search for the Production of Scalar Bottom Quarks inpp¯Collisions ats=1.96  TeV

2010

We report on a search for direct scalar bottom quark (sbottom) pair production in pp collisions at {radical}(s)=1.96 TeV, in events with large missing transverse energy and two jets of hadrons in the final state, where at least one of the jets is required to be identified as originating from a b quark. The study uses a collider detector at Fermilab Run II data sample corresponding to 2.65 fb{sup -1} of integrated luminosity. The data are in agreement with the standard model. In an R-parity conserving minimal supersymmetric scenario, and assuming that the sbottom decays exclusively into a bottom quark and a neutralino, 95% confidence-level upper limits on the sbottom pair production cross se…

QuarkPhysicsParticle physics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyHadronGeneral Physics and AstronomySupersymmetry7. Clean energy01 natural sciencesBottom quarkNuclear physicsPair production0103 physical sciencesNeutralinoGrand Unified TheoryHigh Energy Physics::Experiment010306 general physicsCollider Detector at FermilabPhysical Review Letters
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Search forBs0→μ+μ−andB0→μ+μ−Decays with CDF II

2011

A search has been performed for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays using 7 fb{sup -1} of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B{sup 0} candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 6.0 x 10{sup -9} at 95% confidence level. We observe an excess of B{sub s}{sup 0} candidates. The probability that the background processes alone could produce such an excess or larger is 0.27%. The probability that the combination of background and the expe…

Flight directionNuclear and High Energy PhysicsParticle physicsMesonTevatronGeneral Physics and Astronomy01 natural sciences7. Clean energyLuminosityStandard Modellaw.inventionNuclear physicsParticle decaychemistry.chemical_compoundlawTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY0103 physical sciencesInvariant massLimit (mathematics)FermilabCollider010306 general physicsPhysicsMuon010308 nuclear & particles physicsBranching fractionSupersymmetryD0 experimentIMesCrystallographychemistryDecay lengthHigh Energy Physics::ExperimentLeptonPhysical Review Letters
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Search for the Production of Narrowtb¯Resonances in1.9  fb−1ofpp¯Collisions ats=1.96  TeV

2009

We present new limits on resonant tb production in ppbar collisions at sqrt(s) = 1.96 TeV, using 1.9 fb{sup -1} of data recorded with the CDF II detector at the Fermilab Tevatron. We reconstruct a putative tb mass in events with a lepton, neutrino candidate, and two or three jets, and search for anomalous tb production as modeled by W{prime} {yields} tb. We set a new limit on a right-handed W{prime} with standard model-like coupling, excluding any mass below 800 GeV at 95% C.L. For any narrow W{prime}-like state with mass above 800 GeV, the cross-section is found to be less than 0.28 pb at 95% C.L. We also present an exclusion of the W{prime} coupling strength versus W{prime} mass.

PhysicsParticle physics010308 nuclear & particles physicsTevatronGeneral Physics and AstronomyCoupling (probability)01 natural sciencesPrime (order theory)Standard ModelNuclear physics0103 physical sciencesHigh Energy Physics::ExperimentProduction (computer science)FermilabNeutrino010306 general physicsLeptonPhysical Review Letters
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Measurement ofW-Boson Polarization in Top-Quark Decay inpp¯Collisions ats=1.96  TeV

2010

We report measurements of the polarization of W bosons from top-quark decays using 2.7 fb(-1) of p (p) over bar collisions collected by the CDF II detector. Assuming a top-quark mass of 175 GeV/c(2), three measurements are performed. A simultaneous measurement of the fraction of longitudinal (f(0)) and right-handed (f(0)) W bosons yields the model- independent results f(0) =0. 88 +/- 0.11(stat) +/- 0.06(syst) and f(+) = 0.15 +/- 0.07(stat) +/- 0.06(syst) with a correlation coefficient of -0.59. A measurement of f(0) [f(+)] constraining f(+) [f(0)] to its standard model value of 0.0 [0.7] yields f(0) 0.70 + 0.07(stat) +/- 0.04(syst) [f(+) - 0.01 +/- 0.02(stat) +/- 0.05(syst)]. All these resu…

QuarkPhysicsParticle physicsTop quark010308 nuclear & particles physicsGeneral Physics and AstronomyElementary particleFermion01 natural sciencesHelicityNuclear physicsPair production0103 physical sciencesGrand Unified Theory010306 general physicsBosonPhysical Review Letters
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Search for the neutral current top quark decayt→Zcusing the ratio ofZ-boson+4  jetstoW-boson+4  jetsproduction

2009

We have used the Collider Detector at Fermilab (CDF II) to search for the flavor-changing neutral-current (FCNC) top quark decay t {yields} Zc using a technique employing ratios of W and Z production, measured in p{bar p} data corresponding to an integrated luminosity of 1.52 fb{sup -1}. The analysis uses a comparison of two decay chains, p{bar p} {yields} t{bar t} {yields} WbWb {yields} {ell}{nu}bjjb and p{bar p} {yields} t{bar t} {yields} ZcWb {yields} {ell}{ell}cjjb, to cancel systematic uncertainties in acceptance, efficiency, and luminosity. We validate the modeling of acceptance and efficiency for lepton identification over the multi-year dataset using another ratio of W and Z product…

QuarkPhysicsNuclear and High Energy PhysicsTop quarkParticle physicsNeutral current010308 nuclear & particles physicsBranching fractionHigh Energy Physics::Phenomenology7. Clean energy01 natural sciencesStandard ModelNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::ExperimentProduction (computer science)010306 general physicsCollider Detector at FermilabPhysical Review D
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Observation of theΩb−baryon and measurement of the properties of theΞb−andΩb−baryons

2009

The authors report the observation of the bottom, doubly-strange baryon {Omega}{sub b}{sup -} through the decay chain {Omega}{sub b}{sup -} {yields} J/{psi}{Omega}{sup -}, where J/{psi} {yields} {mu}{sup +} {mu}{sup -}, {Omega}{sup -} {yields} {Lambda}K{sup -}, and {Lambda} {yields} p {pi}{sup -}, using 4.2 fb{sup -1} of data from p{bar p} collisions at {radical}s = 1.96 TeV, and recorded with the Collider Detector at Fermilab. A signal is observed whose probability of arising from a background fluctuation is 4.0 x 10{sup -8}, or 5.5 Gaussian standard deviations. The {Omega}{sub b}{sup -} mass is measured to be 6054.4 {+-} 6.8(stat.) {+-} 0.9(syst.) MeV/c{sup 2}. The lifetime of the {Omega}…

PhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsLambda01 natural sciencesOmegaBaryonParticle decayCrystallography0103 physical sciencesTransverse momentumHigh Energy Physics::ExperimentNuclear Experiment010306 general physicsCollider Detector at FermilabPhysical Review D
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Measurement of the Ratioσtt¯/σZ/γ*→lland Precise Extraction of thett¯Cross Section

2010

We report a measurement of the ratio of the t (t) over bar to Z/gamma* production cross sections in root s = 1.96 TeV p (p) over bar collisions using data corresponding to an integrated luminosity of up to 4.6 fb(-1), collected by the CDF II detector. The t (t) over bar cross section ratio is measured using two complementary methods, a b-jet tagging measurement and a topological approach. By multiplying the ratios by the well-known theoretical Z/gamma* -> ll cross section predicted by the standard model, the extracted t (t) over bar cross sections are effectively insensitive to the uncertainty on luminosity. A best linear unbiased estimate is used to combine both measurements with the resul…

PhysicsParticle physicsLuminosity (scattering theory)010308 nuclear & particles physicsBar (music)Astrophysics::High Energy Astrophysical PhenomenaHigh Energy Physics::PhenomenologyGeneral Physics and AstronomyElementary particleFermion01 natural sciencesParticle detectorStandard ModelNuclear physicsCross section (physics)0103 physical sciencesMeasuring instrumentHigh Energy Physics::Experiment010306 general physicsPhysical Review Letters
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Measurement of the top quark mass andpp¯→tt¯cross section in the all-hadronic mode with the CDF II detector

2010

We present a measurement of the top quark mass and of the top-antitop pair production cross section using p-pbar data collected with the CDFII detector at the Tevatron Collider at the Fermi National Accelerator Laboratory and corresponding to an integrated luminosity of 2.9 fb-1. We select events with six or more jets satisfying a number of kinematical requirements imposed by means of a neural network algorithm. At least one of these jets must originate from a b quark, as identified by the reconstruction of a secondary vertex inside the jet. The mass measurement is based on a likelihood fit incorporating reconstructed mass distributions representative of signal and background, where the abs…

PhysicsQuarkNuclear and High Energy PhysicsParticle physicsTop quarkMass distribution010308 nuclear & particles physicsHadronTevatron01 natural sciencesBottom quarkNuclear physicsPair production0103 physical sciencesMass spectrumHigh Energy Physics::Experiment010306 general physicsPhysical Review D
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Search for ExclusiveZ-Boson Production and Observation of High-Masspp¯→pγγp¯→pl+l−p¯Events inpp¯Collisions ats=1.96  TeV

2009

We present a search for exclusive Z boson production in proton-antiproton collisions at {radical}s = 1.96 TeV, using the CDF II detector at Fermilab. We observe no exclusive Z {yields} {ell}{sup +}{ell}{sup -} candidates and place the first upper limit on the exclusive Z cross section in hadron collisions, {sigma}{sub excl}(Z) 40 GeV=c{sup 2} and |{eta}{sub {ell}}| < 4 to be {sigma} = 0.24{sub -0.10}{sup +0.13} pb, which is the first measurement for this mass range and is consistent with the standard model prediction.

PhysicsParticle physics010308 nuclear & particles physicsHadronGeneral Physics and AstronomySigmaElementary particle01 natural sciences7. Clean energyStandard ModelNuclear physics0103 physical sciencesGrand Unified TheoryHigh Energy Physics::ExperimentProduction (computer science)Quantum field theoryNuclear Experiment010306 general physicsBosonPhysical Review Letters
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Search for New Physics with a Dijet Plus MissingETSignature inpp¯Collisions ats=1.96  TeV

2010

We present results of a signature-based search for new physics using a dijet plus missing transverse energy (E{sub T}) data sample collected in 2 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV with the CDF II detector at the Fermilab Tevatron. We observe no significant event excess with respect to the standard model prediction and extract a 95% C.L. upper limit on the cross section times acceptance for a potential contribution from a non-standard model process. Based on this limit the mass of a potential first or second generation scalar leptoquark is constrained to be above 187 GeV/c{sup 2}.

PhysicsParticle physics010308 nuclear & particles physicsPhysics beyond the Standard ModelHigh Energy Physics::PhenomenologyScalar (mathematics)TevatronGeneral Physics and Astronomy01 natural sciencesStandard ModelNuclear physics0103 physical sciencesHigh Energy Physics::ExperimentLeptoquarkLimit (mathematics)Fermilab010306 general physicsEnergy (signal processing)Physical Review Letters
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Top quark mass measurement in thett¯all hadronic channel using a matrix element technique inpp¯collisions ats=1.96  TeV

2009

We present a measurement of the top quark mass in the all hadronic channel ($t\overline{t}\ensuremath{\rightarrow}b\overline{b}{q}_{1}{\overline{q}}_{2}{q}_{3}{\overline{q}}_{4}$) using $943\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ of $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ collected at the CDF II detector at Fermilab (CDF). We apply the standard model production and decay matrix element (ME) to $t\overline{t}$ candidate events. We calculate per-event probability densities according to the ME calculation and construct template models of signal and background. The scale of the jet energy is calibrated using additional templates formed with the invaria…

PhysicsNuclear and High Energy PhysicsParticle physicsTop quark010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyHadronJet (particle physics)01 natural sciencesStandard ModelNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::ExperimentProduction (computer science)Invariant mass010306 general physicsEnergy (signal processing)Physical Review D
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Search for New Bottomlike Quark Pair DecaysQQ¯→(tW∓)(t¯W±)in Same-Charge Dilepton Events

2010

We report the most restrictive direct limits on masses of fourth-generation down-type quarks b{sup '}, and quarklike composite fermions (B or T{sub 5/3}), decaying promptly to tW{sup +}-. We search for a significant excess of events with two same-charge leptons (e, mu), several hadronic jets, and missing transverse energy. An analysis of data from pp collisions with an integrated luminosity of 2.7 fb{sup -1} collected with the CDF II detector at Fermilab yields no evidence for such a signal, setting mass limits m{sub b}{sup '}, m{sub B}>338 GeV/c{sup 2} and m{sub T{sub 5{sub /{sub 3}}}}>365 GeV/c{sup 2} at 95% confidence level.

QuarkPhysicsParticle physics010308 nuclear & particles physicsHadronGeneral Physics and AstronomyElementary particleFermion01 natural sciencesLuminosityNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsEnergy (signal processing)LeptonPhysical Review Letters
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Searching the inclusiveℓγE̸T+b-quark signature for radiative top quark decay and non-standard-model processes

2009

We compare the inclusive production of events containing a lepton (l), a photon ({gamma}), significant transverse momentum imbalance (Ee{sub T}), and a jet identified as containing a b-quark, to SM predictions. The search uses data produced in proton-antiproton collisions at {radical}(s)=1.96 TeV corresponding to 1.9 fb{sup -1} of integrated luminosity taken with the CDF detector. We find 28 l{gamma}bEe{sub T} events versus an expectation of 31.0{sub -3.5}{sup +4.1} events. If we further require events to contain at least three jets and large total transverse energy, the largest SM source is radiative top-quark pair production, tt+{gamma}. In the data we observe 16 tt{gamma} candidate event…

PhysicsNuclear and High Energy PhysicsParticle physicsTop quark010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaElementary particle01 natural sciences7. Clean energyBottom quarkNuclear physicsParticle decayPair production0103 physical sciencesHigh Energy Physics::ExperimentProduction (computer science)010306 general physicsEnergy (signal processing)LeptonPhysical Review D
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Measurement ofZγproduction inpp¯collisions ats=1.96  TeV

2010

The production rate and kinematics of photons produced in association with Z bosons are studied using 2 fb{sup -1} of p{bar p} collision data collected at the Collider Detector at Fermilab. The cross section for p{bar p} {yields} {ell}{sup +}{ell}{sup -}{gamma} + X (where the leptons {ell} are either muons or electrons with dilepton mass M{sub {ell}{ell}} > 40 GeV/c{sup 2}, and where the photon has transverse energy E{sub T}{sup {gamma}} > 7 GeV and is well separated from the leptons) is 4.6 {+-} 0.2 (stat) {+-} 0.3 (syst) {+-} 0.3 (lum) pb, which is consistent with standard model expectations. We use the photon ET distribution from Z{gamma} events where the Z has decayed to {mu}{sup +}{mu}…

PhysicsNuclear and High Energy PhysicsAntiparticleParticle physicsMuon010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyElementary particle7. Clean energy01 natural sciencesNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::ExperimentProduction (computer science)010306 general physicsCollider Detector at FermilabEnergy (signal processing)LeptonPhysical Review D
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Search for the Higgs Boson Produced in Association withZ→ℓ+ℓ−inpp¯Collisions ats=1.96  TeV

2009

We present a search for associated production of the standard model (SM) Higgs boson and a Z boson where the Z boson decays to two leptons and the Higgs decays to a pair of b quarks in p{bar p} collisions at the Fermilab Tevatron. We use event probabilities based on SM matrix elements to construct a likelihood function of the Higgs content of the data sample. In a CDF data sample corresponding to an integrated luminosity of 2.7 fb{sup -1} we see no evidence of a Higgs boson with a mass between 100 GeV/c{sup 2} and 150 GeV/c{sup 2}. We set 95% confidence level (C.L.) upper limits on the cross-section for ZH production as a function of the Higgs boson mass m{sub H}; the limit is 8.2 times the…

QuarkPhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyTevatronCenter (category theory)General Physics and AstronomyElementary particle01 natural sciencesSearch for the Higgs bosonStandard ModelNuclear physicsParticle decayContent (measure theory)0103 physical sciencesHiggs bosonHigh Energy Physics::ExperimentProduction (computer science)010306 general physicsCollider Detector at FermilabLeptonBosonPhysical Review Letters
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Search for Gluino-Mediated Bottom Squark Production inpp¯Collisions ats=1.96  TeV

2009

We report on a search for the supersymmetric partner of the bottom quark produced from gluino decays in data from 2.5 fb{sup -1} of integrated luminosity collected by the Collider Detector at Fermilab at {radical}s = 1.96 TeV. Candidate events are selected requiring two or more jets and large missing transverse energy. At least two of the jets are required to be tagged as originating from a b quark to enhance the sensitivity. The results are in good agreement with the prediction of the standard model processes, giving no evidence for gluino decay to sbottom quarks. This result constrains the gluino-pair-production cross section to be less than 40 fb at 95% credibility level for a gluino mas…

QuarkPhysicsParticle physicsGluino010308 nuclear & particles physicsHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyGeneral Physics and AstronomySuperpartnerSupersymmetry01 natural sciences7. Clean energyBottom quarkStandard ModelNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::Experiment010306 general physicsCollider Detector at FermilabPhysical Review Letters
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First simultaneous measurement of the top quark mass in thelepton+jetsand dilepton channels at CDF

2009

We present a measurement of the mass of the top quark using data corresponding to an integrated luminosity of 1.9 fb{sup -1} of pp collisions collected at {radical}(s)=1.96 TeV with the CDF II detector at Fermilab's Tevatron. This is the first measurement of the top quark mass using top-antitop pair candidate events in the lepton+jets and dilepton decay channels simultaneously. We reconstruct two observables in each channel and use a nonparametric kernel density estimation technique to derive two-dimensional probability density functions from simulated signal and background samples. The observables are the top quark mass and the invariant mass of two jets from the W decay in the lepton+jets…

PhysicsNuclear and High Energy PhysicsTop quarkParticle physics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyHadronTevatronJet (particle physics)01 natural sciencesBottom quarkNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::ExperimentInvariant mass010306 general physicsLeptonPhysical Review D
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Observation of the rare B(s)(0) + decay from the combined analysis of CMS and LHCb data.

2015

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported licence.-- et al.

fundamental particleCompact Muon Solenoidstandard model flavor changing neutral currentsradioisotope decayB physicGaussian methodMU(+)MU(-)Temel Bilimler (SCI)rare decay [B/s0]Elementary particleATLAS DETECTOR12.15.MmÇOK DİSİPLİNLİ BİLİMLERRARE B-MESON DECAYS7000 GeV-cms8000 GeV-cmsSettore ING-INF/01 - Elettronica01 natural sciences7. Clean energyddc:0702 CHARGED LEPTONSscattering [p p]High energy physics ; Experimental particle physics ; LHC ; CMS ; Standard ModelQC[Anahtar Kelime Yok]Large Hadron ColliderMedicine (all); Multidisciplinarystandard3. Good healthHigh Energy Physics - PhenomenologyCERN LHC CollFIS/01 - FISICA SPERIMENTALEpriority journalHiggs bosonScience & Technology - Other TopicsPARTICLE PHYSICSmass spectrum [dimuon]Protonviolationcolliding beams [p p]physicschemical analyzerMesonModels beyond the standard modelprobabilitymesonelectromagnetic radiationB/s0 --> muon+ muon-Nuclear physicsbranching ratio: measured [B0]SEARCHLeptonic semileptonic and radiative decays of bottom mesonRARE B-MESON DECAYS; MINIMAL FLAVOR VIOLATION; LHC; CMS DETECTOR; LHCb DETECTOR; SEARCH; MU(+)MU(-); B-S(0); B-0;B-MESON DECAYS; MINIMAL FLAVOR VIOLATION; 2 CHARGED LEPTONS; ATLAS; DETECTOR; SEARCH; MU(+)MU(-); B-S(0); B-0; COLLIDER; PARTICLE010306 general physicsScience & TechnologyMuonMULTIDISCIPLINARY SCIENCES010308 nuclear & particles physicsBranching fractionMeson Bnull hypothesisDoğa Bilimleri GenelElementary particlesLARGE HADRON COLLIDERHEPp(p)over-bar collisionsNATURAL SCIENCES GENERALrare decay [B0]13.20.HeMINIMAL FLAVOR VIOLATIONchemical analysisprecisionB0 --> muon+ muon-Física de partículesExperimental particle physicsleptonic decay [B0]Physics::Instrumentation and DetectorsPhysics beyond the Standard ModelB-meson decays; p(p)over-bar collisions; branching fraction; root-s=1.96 tev; search; mu(+)mu(-); b-0; b-s(0); violation; modelsLarge Hadron Collider (LHC)High Energy Physics - ExperimentSettore FIS/04 - Fisica Nucleare e SubnucleareNeutral currentCOLLIDER[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]uncertainty12.60.-iFlavour Physicmass spectrometryPhysicsExperimental particleMultidisciplinaryCMSMedicine (all)Temel BilimlerSettore FIS/01 - Fisica SperimentaleB-meson decaysATLASLarge Hadron Collider beautybranching ratio: measured [B/s0]root-s=1.96 tevNatural Sciences (SCI)LHCNatural SciencesPARTICLEdata processingParticle Physics - Experimentchemical reactionParticle physicsbranching fractionNOPARTICLE PHYSICS; LARGE HADRON COLLIDER; CMS; LHCBmodelsLHCBExperimental particle; physics; data processing; electromagnetic field; electromagnetic radiation; fundamental particle; Gaussian method; physics; precision; chemical analysis; chemical analyzer; chemical reaction; elementary particle; Large Hadron Collider beauty; mass spectrometry; meson; null hypothesis; prediction; priority journal; probability; radioisotope decay; standard; uncertainty;B-MESON DECAYSelectromagnetic fieldTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYRare Decay0103 physical sciencesElectromagnetic fieldB-0elementary particleSDG 7 - Affordable and Clean EnergyDETECTORCompact Muon SolenoidMultidisipliner/dk/atira/pure/sustainabledevelopmentgoals/affordable_and_clean_energyLHCb DETECTORCMS LHC Meson B Rare DecayMinimal flavor violationpredictionLeptonsLHC-Bleptonic decay [B/s0]LHCbRare decayMedicine (all) MultidisciplinaryRARE B-MESON DECAYS; MINIMAL FLAVOR VIOLATION; LHC; CMS DETECTOR; LHCb DETECTOR; SEARCH; MU(+)MU(-); B-S(0); B-0B-S(0)[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]High Energy Physics::ExperimentExperimentsexperimental resultsCMS DETECTOR
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