0000000000160945

AUTHOR

S. Mcmahon

showing 11 related works from this author

Study of Time-DependentCPAsymmetry in NeutralBDecays toJ/ψπ0

2003

We present the first study of the time-dependent CP-violating asymmetry in B0-->J/psi pi(0) decays using e(+)e(-) annihilation data collected with the BABAR detector at the Upsilon(4S) resonance during the years 1999-2002 at the PEP-II asymmetric-energy B Factory at SLAC. Using approximately 88 x 10(6) BB; pairs, our results for the coefficients of the cosine and sine terms of the CP asymmetry are C(J/psi pi(0))=0.38+/-0.41(stat)+/-0.09(syst) and S(J/psi pi(0))=0.05+/-0.49(stat)+/-0.16(syst).

PhysicsParticle physicsAnnihilation010308 nuclear & particles physicsmedia_common.quotation_subjectGeneral Physics and AstronomyResonanceAstrophysics::Cosmology and Extragalactic Astrophysics01 natural sciencesAsymmetryB-factoryNuclear physicsParticle decay0103 physical sciencesPiHigh Energy Physics::ExperimentAstrophysics::Earth and Planetary Astrophysics010306 general physicsmedia_commonPhysical Review Letters
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Measurement of the Inclusive Charmless Semileptonic Branching Ratio ofBMesons and Determination of|Vub|

2004

We report a measurement of the inclusive charmless semileptonic branching fraction of B mesons in a sample of 89 x 10(6) (-)BB events recorded with the BABAR detector at the Upsilon(4S) resonance. Events are selected by fully reconstructing the decay of one B meson and identifying a charged lepton from the decay of the other B meson. The number of signal events is extracted from the mass distribution of the hadronic system accompanying the lepton and is used to determine the ratio of branching fractions B((-)B-->X(u)lnu;)/B((-)B-->Xlnu;)=[2.06+/-0.25(stat)+/-0.23(syst)+/-0.36(theo)]x10(-2). Using the measured branching fraction for inclusive semileptonic B decays, we find B((-)B-->X(u)lnu;)…

PhysicsHigh energyParticle physics010308 nuclear & particles physicsBranching fractionElectron–positron annihilationHadronGeneral Physics and Astronomy01 natural sciencesNuclear physics0103 physical sciencesMass spectrumMatrix elementB meson010306 general physicsLeptonPhysical Review Letters
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Evidence forB+→J/ψpΛ¯and Search forB0→J/ψpp¯

2003

We have performed a search for the decays ${B}^{+}\ensuremath{\rightarrow}J/\ensuremath{\psi}p\overline{\ensuremath{\Lambda}}$ and ${B}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}p\overline{p}$ in a data set of $(88.9\ifmmode\pm\else\textpm\fi{}1.0)\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $\ensuremath{\Upsilon}(4S)$ decays collected by the BABAR experiment at the PEP-II ${e}^{+}{e}^{\ensuremath{-}}$ storage ring at the Stanford Linear Accelerator Center. Four charged $B$ candidates have been observed with an expected background of $0.21\ifmmode\pm\else\textpm\fi{}0.14$ events. The corresponding branching fraction is $({12}_{\ensuremath{-}6}^{+9})\ifmmode\times\else\texttimes\fi{}{10}^…

CombinatoricsPhysicsParticle decay010308 nuclear & particles physicsBranching fraction0103 physical sciencesCenter (category theory)General Physics and Astronomy010306 general physics01 natural sciencesEngineering physicsPhysical Review Letters
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Search for the Radiative DecaysB→ργandB0→ωγ

2004

A search for the exclusive radiative decays B {yields} {rho}(770){gamma} and B{sup 0} {yields} {omega}(782){gamma} is performed on a sample of about 84 million B{bar B} events collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. No significant signal is seen in any of the channels. We set upper limits on the branching fractions {Beta} of {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) < 1.2 x 10{sup -6}, {Beta}(B{sup +} {yields} {rho}{sup +}{gamma}) < 2.1 x 10{sup -6}, and {Beta}(B{sup 0} {yields} {omega}{gamma}) < 1.0 x 10{sup -6} at 90% confidence level (C.L.). Using the assumption that {Lambda}(B {yields} {rho}{gamma}) = {Lambda}(B{sup +} {yields} …

Physics010308 nuclear & particles physicsBranching fractionElectron–positron annihilationRadiative decayGeneral Physics and Astronomy01 natural sciencesOmegaCrystallography0103 physical sciencesRadiative transferB mesonAtomic physics010306 general physicsPhysical Review Letters
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Association Between Tumor Egfr and Kras Mutation Status and Clinical Outcomes in Nsclc Patients Randomized to Sorafenib Plus Best Supportive Care (BS…

2012

ABSTRACT Background Tumor EGFR and KRas mutations are both predictive and prognostic biomarkers in patients with advanced NSCLC. We analyzed the correlation between these biomarkers and treatment outcomes in a phase III trial of 3rd/4th line sorafenib in patients with NSCLC. Methods The global, randomized, placebo-controlled MISSION trial enrolled 703 patients with advanced relapsed/refractory NSCLC of predominantly non-squamous histology. The primary study endpoint was overall survival (OS). EGFR and KRas mutations were analyzed in archival tumor samples and in circulating tumor DNA isolated from plasma. Results Tumor and/or plasma mutation data were available from 347 patients (49%). EGFR…

OncologySorafenibmedicine.medical_specialtyProportional hazards modelbusiness.industryHematologymedicine.disease_causePlacebomedicine.diseaseBreast cancerOncologyEgfr mutationInternal medicineMedicineBiomarker (medicine)KRASStage (cooking)businessmedicine.drugAnnals of Oncology
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Impact of clinical phenotypes on management and outcomes in European atrial fibrillation patients: a report from the ESC-EHRA EURObservational Resear…

2021

Abstract Background Epidemiological studies in atrial fibrillation (AF) illustrate that clinical complexity increase the risk of major adverse outcomes. We aimed to describe European AF patients’ clinical phenotypes and analyse the differential clinical course. Methods We performed a hierarchical cluster analysis based on Ward’s Method and Squared Euclidean Distance using 22 clinical binary variables, identifying the optimal number of clusters. We investigated differences in clinical management, use of healthcare resources and outcomes in a cohort of European AF patients from a Europe-wide observational registry. Results A total of 9363 were available for this analysis. We identified three …

RegistrieResearch Reportmedicine.medical_specialtyMajor adverse outcomeCardiovascular risk factorsCluster analysisRisk FactorsInternal medicineClinical phenotypeAtrial FibrillationEpidemiologyHumansMedicineRegistriesCluster analysiAtrial fibrillation; Clinical management; Clinical phenotypes; Cluster analysis; Major adverse outcomes; Humans; Phenotype; Registries; Research Report; Risk Factors; Atrial FibrillationClinical managementbusiness.industryProportional hazards modelRisk FactorHazard ratioRAtrial fibrillationClinical phenotypesMajor adverse outcomesGeneral Medicinemedicine.diseaseAtrial fibrillationConfidence intervalPhenotypeCohortMedicineObservational studybusinessResearch ArticleHumanBMC Medicine
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Limits onD0−D¯0Mixing andCPViolation from the Ratio of Lifetimes for Decay toK−π+,K−K+, andπ−π+

2003

We present a measurement of D0-macro D0 mixing parameters using the ratios of lifetimes extracted from samples of D0 mesons decaying to K-pi(+), K-K+, and pi(-)pi(+). Using 91 fb(-1) of data collected by the BABAR detector at the PEP-II asymmetric-energy B Factory, we obtain a value Y=[0.8+/-0.4(stat.)(+0.5)(-0.4)(syst.)]%, which, in the limit of CP conservation, corresponds to the mixing parameter y=Delta Gamma/2 Gamma. Using the difference in lifetimes of D0 and macro D0 mesons, we obtain the CP-violation parameter Delta Y=[-0.8+/-0.6(stat.)+/-0.2(syst.)]%.

PhysicsMeson010308 nuclear & particles physicsElectron–positron annihilationAnalytical chemistryGeneral Physics and AstronomyValue (computer science)01 natural sciencesB-factoryNuclear physicsParticle decay0103 physical sciencesPiCP violationHigh Energy Physics::Experiment010306 general physicsMixing (physics)Physical Review Letters
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The BaBar detector: Upgrades, operation and performance

2013

The BABAR detector operated successfully at the PEP-Il asymmetric e(+) e(-) collider at the SLAC National Accelerator Laboratory from 1999 to 2008. This report covers upgrades, operation, and performance of the collider and the detector systems, as well as the trigger, online and offline computing, and aspects of event reconstruction since the beginning of data taking.

Online and offlinePhysics - Instrumentation and DetectorsGeneral-purpose detector for colliding beamPhysics::Instrumentation and DetectorsBABARSettore ING-INF/01 - Elettronica01 natural sciences/dk/atira/pure/sustainabledevelopmentgoals/clean_water_and_sanitationlaw.inventionHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)lawBeam monitoringPEP2[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Ream monitoringInstrumentationQCEvent reconstructionPhysicsoperational experience; high-luminosity storage ring operation; beam monitoring; general-purpose detector for colliding beamsGeneral-purpose detector for colliding beamsDetectorElectrical engineeringInstrumentation and Detectors (physics.ins-det)upgrade [detector]:Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431 [VDP]Beam monitoring; General-purpose detector for colliding beams; High-luminosity storage ring operation; Operational experience; Nuclear and High Energy Physics; InstrumentationPARTICLE PHYSICSFísica nuclearPARTICLE PHYSICS;PEP2;BABARSDG 6 - Clean Water and SanitationperformanceNuclear and High Energy PhysicsFOS: Physical sciencesNuclear physics0103 physical sciencesddc:530[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]010306 general physicsCollideractivity report010308 nuclear & particles physicsbusiness.industryHigh-luminosity storage ring operation:Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431 [VDP]Operational experienceExperimental High Energy PhysicsBaBarPhysics::Accelerator PhysicsHigh Energy Physics::Experimentbusiness
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Measurements of the branching fractions and bounds on the charge asymmetries of charmless three-body charged B decays.

2003

We present measurements of branching fractions and charge asymmetries for charmless B-meson decays to three-body final states of charged pions and kaons. The analysis uses 81.8 fb^-1 of data collected at the Upsilon(4S) resonance with the BaBar detector at the SLAC PEP-II asymmetric B Factory. We measure the branching fractions B(B+ -&gt; pi+ pi- pi+) = (10.9 +/- 3.3 +/- 1.6) x 10^-6, B(B+ -&gt; K+ pi- pi+) = (59.1 +/- 3.8 +/- 3.2) x 10^-6, and B(B+ -&gt; K+ K- K+) = (29.6 +/- 2.1 +/- 1.6) x 10^-6, and provide 90% C.L. upper limits for other decays. We observe no charge asymmetries for these modes.

Particle physicsMesonBABARHadronCharged particleGeneral Physics and AstronomyFOS: Physical sciencesElementary particlePARTICLE PHYSICS; PEP2; BABAR01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsParticle decayHigh Energy Physics - Experiment (hep-ex)PionSEARCH0103 physical sciencesPEP2[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]B meson010306 general physicsProbabilityPhysics010308 nuclear & particles physicsBranching fractionCerenkov counterComputer simulationB-factoryMonte Carlo methodParticle beamNuclear physicPARTICLE PHYSICSBranching fractionStorage ringParticle beam trackingPhysical review letters
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Observation of a Narrow Meson State Decaying toDs+π0at a Mass of2.32  GeV/c2

2003

We have observed a narrow state near 2.32 GeV/c(2) in the inclusive D(+)(s)pi(0) invariant mass distribution from e(+)e(-) annihilation data at energies near 10.6 GeV. The observed width is consistent with the experimental resolution. The small intrinsic width and the quantum numbers of the final state indicate that the decay violates isospin conservation. The state has natural spin-parity and the low mass suggests a J(P)=0(+) assignment. The data sample corresponds to an integrated luminosity of 91 fb(-1) recorded by the BABAR detector at the SLAC PEP-II asymmetric-energy e(+)e(-) storage ring.

PhysicsParticle physicsAnnihilationMeson010308 nuclear & particles physicsElectron–positron annihilationGeneral Physics and AstronomyQuantum number7. Clean energy01 natural sciencesLuminosityNuclear physicsParticle decayIsospin0103 physical sciencesHigh Energy Physics::ExperimentInvariant mass010306 general physicsPhysical Review Letters
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Observation of the DecayB±→π±π0, Study ofB±→K±π0, and Search forB0→π0π0

2003

We present results for the branching fractions and charge asymmetries in B+/--->h(+/-)pi(0) (where h(+/-)=pi(+/-),K+/-) and a search for the decay B0-->pi(0)pi(0) using a sample of approximately 88 x 10(6) BBmacr; pairs collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure B(B+/--->pi(+/-)pi(0))=(5.5(+1.0)(-0.9)+/-0.6)x10(-6), where the first error is statistical and the second is systematic. The B+/--->pi(+/-)pi(0) signal has a significance of 7.7sigma including systematic uncertainties. We simultaneously measure the K+/-pi(0) branching fraction to be B(B+/--->K+/-pi(0))=(12.8(+1.2)(-1.1)+/-1.0)x10(-6). The charge asymmetries are Api(+/-)(pi(0))=-0.0…

PhysicsMeson010308 nuclear & particles physicsBranching fractionElectron–positron annihilationHadronAnalytical chemistryGeneral Physics and Astronomy01 natural sciencesParticle decayTheoretical physicsPion0103 physical sciencesPiB meson010306 general physicsPhysical Review Letters
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