0000000000323441

AUTHOR

A. M. Merchant

showing 9 related works from this author

Measurement of the total width, the electronic width, and the mass of theΥ(10580)resonance

2005

We present a measurement of the parameters of the Υ(10580) resonance based on a dataset collected with the BABAR detector at the SLAC PEP-II asymmetric B factory. We measure the total width Γtot=(20.7±1.6±2.5)  MeV, the electronic partial width Γee=(0.321±0.017±0.029)  keV and the mass M=(10579.3±0.4±1.2)  MeV/c2.

PhysicsNuclear and High Energy Physics010308 nuclear & particles physicsmedia_common.quotation_subjectElectron–positron annihilationDetectorElectronic structure01 natural sciencesAsymmetryResonance (particle physics)Particle identificationB-factoryNuclear physics0103 physical sciencesInvariant massAtomic physics010306 general physicsmedia_commonPhysical Review D
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Measurement of theB→Xsℓ+ℓ−Branching Fraction with a Sum over Exclusive Modes

2004

We present a preliminary measurement of time-dependent We measure the branching fraction for the flavor-changing neutral-current process B -> Xs l+ l- with a sample of 89 x 10^6 Upsilon(4S) -> BBbar events recorded with the BaBar detector at the PEP-II e+e- storage ring. The final state is reconstructed from e+e- or mu+mu- pairs and a hadronic system consisting of one K or K0s and up to two pions, with at most one pi0. We observe a signal of 40 +/- 10(stat) +/- 2(syst) events and extract the inclusive branching fraction B(B -> Xs l+ l-) = (5.6 +/- 1.5(stat) +/- 0.6(exp syst) +/- 1.1(model syst)) x 10^-6 for mll > 0.2 GeV/c^2.

PhysicsParticle physics010308 nuclear & particles physicsBranching fractionElectron–positron annihilationHadronGeneral Physics and Astronomy01 natural sciencesParticle decayPair productionPion0103 physical sciencesB meson010306 general physicsPhysical Review Letters
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Limits on the decay-rate difference of neutralBmesons and onCP,T, andCPTviolation inB0B0oscillations

2004

Using events in which one of two neutral-B mesons from the decay of an {Upsilon}(4S) resonance is fully reconstructed, we set limits on the difference between the decay rates of the two neutral-B mass eigenstates and on CP, T, and CPT violation in B{sup 0}{bar B}{sup 0} mixing. The reconstructed decays, comprising both CP and flavor eigenstates, are obtained from 88 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We determine six independent parameters governing oscillations ({Delta}m, {Delta}{Lambda}/{Lambda}), CPT and CP violation (Re z, Im z), and CP and T violation (Im {lambda}{sub CP}, |q/p|), where {la…

PhysicsNuclear and High Energy PhysicsParticle physicsMeson010308 nuclear & particles physicsResonanceLambda01 natural sciencesStandard ModelB-factoryNuclear physics0103 physical sciencesCP violationB meson010306 general physicsBar (unit)Physical Review D
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Study of theB−→J/ψK−π+π−decay and measurement of theB−→X(3872)K−branching fraction

2005

The authors study the decay B{sup -} {yields} J/{psi}K{sup -}{pi}{sup +}{pi}{sup -} using 117 million B{bar B} events collected at the {Upsilon}(4S) resonance with the BaBar detector at the PEP-II e{sup +}e{sup -} asymmetric-energy storage ring. They measure the branching fractions {Beta}(B{sup -} {yields} J/{psi}K{sup -} {pi}{sup +}{pi}{sup -}) = (116 {+-} 7(stat.) {+-} 9(syst.)) x 10{sup -5} and {Beta}(B{sup -} {yields} X(3872)K{sup -}) x {Beta}(X(3872) {yields} J/{psi}{pi}{sup +}{pi}{sup -}) = (1.28 {+-} 0.41) x 10{sup -5} and find the mass of the X(3872) to be 3873.4 {+-} 1.4MeV/c{sup 2}. They search for the h{sub c} narrow state in the decay B{sup -} {yields} h{sub c} K{sup -}, h{sub c…

Nuclear physicsPhysicsNuclear and High Energy PhysicsCrystallographyParticle decay010308 nuclear & particles physicsBranching fractionTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYElectron–positron annihilation0103 physical sciences010306 general physics01 natural sciencesX(3872)Physical Review D
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Search forB±→[K∓π±]DK±and Upper Limit on theb→uAmplitude inB±→DK±

2004

We search for B±→[K∓π±]DK± decays, where [K∓π±]D indicates that the K∓π± pair originates from the decay of a D0 or D 0. Results are based on 120×106 Υ(4S)→BB decays collected with the BABAR detector at SLAC. We set an upper limit on the ratio RKπ≡ [Γ(B+→[K-π+]DK+)+Γ(B-→[K+π-]DK-)]/[Γ(B+→[K+π-]DK+)+Γ(B-→[K-π+]DK-)]<0.026 (90%   C.L.). This constrains the amplitude ratio rB≡ |A(B-→D 0K-)/A(B-→D0K-)|<0.22 (90% C.L.), consistent with expectations. The small value of rB favored by our analysis suggests that the determination of the Cabibbo-Kobayashi-Maskawa phase γ from B→DK will be difficult.

Physics010308 nuclear & particles physicsElectron–positron annihilationAnalytical chemistryGeneral Physics and AstronomyValue (computer science)Width ratio01 natural sciencesAmplitude ratioParticle decayAmplitudeClassical mechanics0103 physical sciencesLimit (mathematics)010306 general physicsPhysical Review Letters
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Measurements ofCP-Violating Asymmetries inB0→Ks0π0Decays

2007

The authors present measurements of CP-violating asymmetries in the decay B{sup 0} {yields} a{sub 1}{sup {+-}}(1260){pi}{sup {-+}} with a{sub 1}{sup {+-}}(1260) {yields} {pi}{sup {-+}}{pi}{sup {+-}}{pi}{sup {+-}}. The data sample corresponds to 384 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric B-factory at SLAC. They measure the CP-violating asymmetry {Alpha}{sub CP}{sup a{sub 1}{pi}} = -0.07 {+-} 0.07 {+-} 0.02, the mixing-induced CP violation parameter S{sub a{sub 1}{pi}} = 0.37 {+-} 0.21 {+-} 0.07, the direct Cp violation parameter C{sub a{sub 1}{pi}} = -0.10 {+-} 0.15 {+-} 0.09, and the parameters {Delta}C{sub a{sub 1}{pi}} = 0.26 {+-} 0.15 {+-} 0…

PhysicsParticle physicsUnitarity010308 nuclear & particles physicsmedia_common.quotation_subjectElectron–positron annihilationGeneral Physics and Astronomy01 natural sciencesAsymmetryB-factoryNuclear physicsParticle decayCrystallography0103 physical sciencesCP violation010306 general physicsmedia_commonPhysical Review Letters
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Determination of the Branching Fraction forB→XcℓνDecays and of|Vcb|from Hadronic-Mass and Lepton-Energy Moments

2004

We determine the inclusive B --> Xc l nu branching fraction, the CKM matrix element |Vcb|, and other heavy-quark parameters from a simultaneous fit to moments of the hadronic-mass and lepton-energy distributions in semileptonic B-meson decays, measured as a function of the lower limit on the lepton energy, using data recorded with the BABAR detector. Using Heavy Quark Expansions (HQEs) to order 1/mb^3, we extract BR_cenu=(10.61 +- 0.16(exp) +- 0.06(HQE))% and |Vcb| = (41.4 +- 0.4(exp) +- 0.4(HQE) +- 0.6(th)) 10^-3. The stated errors refer to the experimental, HQE, and additional theoretical uncertainties.

PhysicsParticle physics010308 nuclear & particles physicsBranching fractionCabibbo–Kobayashi–Maskawa matrixElectron–positron annihilationHigh Energy Physics::PhenomenologyHadronGeneral Physics and Astronomy01 natural sciencesStandard ModelNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::ExperimentB meson010306 general physicsLeptonPhysical Review Letters
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Measurement of the Time-DependentCPAsymmetry in theB0→ϕK0Decay

2004

The authors present a measurement of the time-dependent CP asymmetry for the neutral B-meson decay B{sup 0} {yields} {phi} K{sup 0}. They use a sample of approximately 114 million B-meson pairs taken at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B-meson Factory at SLAC. They reconstruct the CP eigenstates {phi}K{sub S}{sup 0} and {phi}K{sub L}{sup 0} where {phi} {yields} K{sup +}K{sup -}, K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}, and K{sub L}{sup 0} is observed via its hadronic interactions. The other B meson in the event is tagged as either a B{sup 0} or {bar B}{sup 0} from its decay products. The values of the CP-violation parameters are S{sub {phi}K} = 0.47 …

PhysicsParticle physics010308 nuclear & particles physicsElectron–positron annihilationmedia_common.quotation_subjectHadronGeneral Physics and AstronomyResonance01 natural sciencesAsymmetryCrystallographyParticle decay0103 physical sciencesCP violationB meson010306 general physicsmedia_commonPhysical 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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