Search results for "baba"

showing 10 items of 93 documents

Search for a light Higgs boson decaying to two gluons orss¯in the radiative decays ofΥ(1S)

2013

We search for the decay Υ(1S)→γA^0, A^0→gg or ss , where A^0 is the pseudoscalar light Higgs boson predicted by the next-to-minimal supersymmetric Standard Model. We use a sample of (17.6±0.3)×10^6 Υ(1S) mesons produced in the BABAR experiment via e^+e^-→Υ(2S)→π^+π^-Υ(1S). We see no significant signal and set 90%-confidence-level upper limits on the product branching fraction B(Υ(1S)→γA^0)·B(A^0→gg or ss) ranging from 10^(-6) to 10^(-2) for A^0 masses in the range 0.5–9.0  GeV/c^2.

PhysicsNuclear and High Energy PhysicsParticle physicsMeson010308 nuclear & particles physicsBranching fractionElectron–positron annihilationBaBar experimentSupersymmetry01 natural sciencesNuclear physicsPseudoscalar0103 physical sciencesHiggs boson010306 general physicsMinimal Supersymmetric Standard ModelPhysical Review D
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Measurement of branching fractions and rate asymmetries in the rare decays B -> K((*))l(+)l(-)

2012

In a sample of 471 million BB events collected with the BABAR detector at the PEP-II e+e- collider we study the rare decays B -> K(*) l+ l-, where l+ l- is either e+e- or mu+mu-. We report results on partial branching fractions and isospin asymmetries in seven bins of di-lepton mass-squared. We further present CP and lepton-flavor asymmetries for di-lepton masses below and above the J/psi resonance. We find no evidence for CP or lepton-flavor violation. The partial branching fractions and isospin asymmetries are consistent with the Standard Model predictions and with results from other experiments.

Nuclear and High Energy PhysicsParticle physicsB-DECAYSElectron–positron annihilationNuclear TheoryB-meson decays; semileptonic B-meson decaysBranching (polymer chemistry)01 natural sciencesResonance (particle physics)law.inventionStandard ModelHigh Energy Physics - ExperimentNuclear physicsB-meson decaylaw0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]PACS: 13.20.He010306 general physicsColliderPhysics010308 nuclear & particles physicsLeptons (Física nuclear)High Energy Physics::PhenomenologyParticle physicsB-meson decaysHEP3. Good healthLeptons (Nuclear physics)IsospinBaBarHigh Energy Physics::Experimentsemileptonic B-meson decaysSDG 6 - Clean Water and SanitationFísica de partículesExperiments
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Measurement of Time-DependentCPAsymmetries and Constraints onsin(2β+γ)with Partial Reconstruction ofB0→D*∓π±Decays

2004

We present a preliminary measurement of the time-dependent CP-violating asymmetry in decays of neutral B mesons to the final states D*-+ pi+- using approximately 178 million BB events recorded by the BaBar experiment at the PEP-II e+e- storage ring. Events containing these decays are selected with a partial reconstruction technique, in which only the high-momentum pi+- from the B decay and the low-momentum pi-+ from the D*-+ decay are used. % We measure the amplitude of the asymmetry to be $-0.041 \pm 0.016 (stat.) \pm 0.010 (syst.)$ and determine bounds on $|\sin(2 \beta + \gamma)|$.

PhysicsParticle physics010308 nuclear & particles physicsElectron–positron annihilationmedia_common.quotation_subjectGeneral Physics and AstronomyBaBar experiment01 natural sciencesAsymmetryBaryonNuclear physicsParticle decayAmplitude0103 physical sciencesCP violationHigh Energy Physics::ExperimentB meson010306 general physicsmedia_commonPhysical Review Letters
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Searches for B0 decays to combinations of charmless isoscalar mesons

2004

We search for B meson decays into two-body combinations of eta, eta', omega, and phi mesons from 89 million B B-bar pairs collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC. We find the branching fraction BF(B0 -> eta omega) = (4.0^{+1.3}_{-1.2} +- 0.4) x 10^-6 with a significance of 4.3 sigma. For all the other decay modes we set the following 90% confidence level upper limits on the branching fractions, in units of 10^-6 : BF(B0 -> eta eta)<2.8, BF(B0 -> eta eta')<4.6, BF(B0 -> eta' eta')<10, BF(B0 -> eta'omega)<2.8, BF(B0 -> eta phi)<1.0, BF(B0 -> eta' phi)<4.5, BF(B0 -> phi phi)<1.5.

IsoscalarElectron–positron annihilationBABARGeneral Physics and AstronomyQCD FACTORIZATION01 natural sciencesOmega13.25.Hw 11.30.Er 12.15.HhHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)Mathematical modelProbability density function[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]PEP2B mesonNuclear ExperimentQCD FACTORIZATION; STANDARD MODEL; BABAR; SLACPhysicsQuantum chromodynamicsSigmaHamiltonianMonte Carlo methodSensitivity analysiPARTICLE PHYSICSBranching fractionSLACParticle physicsMesonSTANDARD MODELQCD FACTORIZATION STANDARD MODELFOS: Physical sciencesLikelihood distributionPARTICLE PHYSICS; PEP2; BABARSolenoidHigh energy physicNuclear physicsPhysics and Astronomy (all)ElectromagnetismElectromagnetic calorimeterPseudoscalar meson0103 physical sciencesPerturbation technique010306 general physicsCalorimeterError analysi010308 nuclear & particles physicsBranching fractionHEPMagnetic fieldHigh Energy Physics::Experiment
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Measurement of the absolute branching fraction of D-0 -> K-pi(+)

2008

We measure the absolute branching fraction for D0 --> K- pi+ using partial reconstruction of B0bar --> D^{*+} X \ell^{-} \bar{\nu}_{\ell} decays, in which only the charged lepton and the pion from the decay D^{*+} --> D0 pi^+ are used. Based on a data sample of 230 million B Bbar pairs collected at the Upsilon(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, we obtain the absolute branching fractions of D0 --> K- pi+ = (4.007 \pm 0.037 \pm 0.072)%, where the first uncertainty is statistical and the second is systematic.

Particle physicsBABARGeneral Physics and Astronomy01 natural sciencesPARTICLE PHYSICS; PEP2; BABARHigh Energy Physics - ExperimentParticle decayPion0103 physical sciencesPEP2[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]measurement;branching;fraction010306 general physicsPhysics010308 nuclear & particles physicsBranching fractionParticle physicsResonanceBABAR detectorD meson; K meson; branching ratioK mesonHEPB-factoryCrystallographyD mesonPair productionPARTICLE PHYSICSHigh Energy Physics::Experimentbranching ratioFísica de partículesExperimentsLeptonBar (unit)
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Branching fraction and charge asymmetry measurements in B→J/ψππ decays

2007

The authors study the decays B{sup 0} {yields} J/{psi} {pi}{sup +}{pi}{sup -} and B{sup +} {yields} J/{psi} {pi}{sup +}{pi}{sup 0}, including intermediate resonances, using a sample of 382 million B{bar B} pairs recorded by the BABAR detector at the PEP-II e{sup +}e{sup -} B factory. They measure the branching fractions {Beta}(B{sup 0} {yields} J/{psi} {rho}{sup 0}) = (2.7 {+-} 0.3 {+-} 0.17) x 10{sup -5} and {Beta}(B{sup +} {yields} J/{psi} {rho}{sup +}) = (5.0 {+-} 0.7 {+-} 0.31) x 10{sup -5}. The authors also set the following upper limits at the 90% confidence level: {Beta}(B{sup 0} {yields} J/{psi} {pi}{sup +}{pi}{sup -} non-resonant) < 1.2 x 10{sup -5}, {Beta}(B{sup 0} {yields} J/{psi…

PhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsBranching fractionElectron–positron annihilationmedia_common.quotation_subjectBABAR detector01 natural sciencesAsymmetryHEPCrystallographyParticle decay0103 physical sciencesBaBar010306 general physicsmedia_common
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Measurement of time-dependentCP-violating asymmetries and constraints onsin(2β+γ)with partial reconstruction ofB→D*∓π±decays

2005

We present a measurement of the time-dependent CP-violating asymmetries in decays of neutral B mesons to the final states D*-+ pi+-, using approximately 232 million BBbar events recorded by the BABAR experiment at the PEP2 e+e- storage ring. Events containing these decays are selected with a partial reconstruction technique, in which only the high-momentum pi+- from the B decay and the low-momentum pi-+ from the D*-+ decay are used. % We measure the parameters related to 2beta+gamma to be a_D*pi=-0.034 +- 0.014 +- 0.009 and c_l_D*pi = -0.019 +- 0.022 +- 0.013. With some theoretical assumptions, we interpret our results in term of the lower limits |\sin(2beta+gamma)|> 0.62 (0.35) at 68% (90%…

PhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsmedia_common.quotation_subjectElectron–positron annihilationBaBar experiment01 natural sciencesAsymmetryNuclear physicsBaryonParticle decay0103 physical sciencesPiCP violationB meson010306 general physicsmedia_commonPhysical Review D
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Precision Measurement of theB→XsγPhoton Energy Spectrum, Branching Fraction, and DirectCPAsymmetryACP(B→Xs+dγ)

2012

The photon spectrum in the inclusive electromagnetic radiative decays of the B meson, B → X_sγ plus B → X_dγ, is studied using a data sample of (382.8±4.2)×10^6Υ(4S) → BB decays collected by the BABAR experiment at SLAC. The spectrum is used to extract the branching fraction B(B → X_sγ)=(3.21±0.33)×10^(-4) for E_γ > 1.8  GeV and the direct CP asymmetry A_(CP)(B → X_(s+d)γ)=0.057±0.063. The effects of detector resolution and Doppler smearing are unfolded to measure the photon energy spectrum in the B meson rest frame.

PhysicsParticle physicsPhoton010308 nuclear & particles physicsBranching fractionmedia_common.quotation_subjectElectron–positron annihilationGeneral Physics and AstronomyBaBar experimentRest framePhoton energy01 natural sciencesAsymmetryNuclear physics0103 physical sciencesB meson010306 general physicsmedia_commonPhysical Review Letters
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Observation and study of the baryonicB-meson decaysB→D(*)pp¯(π)(π)

2012

We present results for B-meson decay modes involving a charm meson, protons, and pions using 455×106 BB pairs recorded by the BaBar detector at the SLAC PEP-II asymmetric-energy e^+e^- collider. The branching fractions are measured for the following ten decays: B ^0→D^0pp, B^0→D^(*0)pp, B^0→D^(*+)ppπ^-, B^0→D^(*+)ppπ^-, B-→D0ppπ^-, B-→D^(*0)ppπ^-, B^0→D^0pp π^-π^+, B^0→D^(*0)pp π^-π^+, B^-→D^+pp π^-π^-, and B^-→D^(*+)pp π^-π^-. The four B^- and the two five-body B^0 modes are observed for the first time. The four-body modes are enhanced compared to the three- and the five-body modes. In the three-body modes, the M(pp) and M(D^((*)0)p) invariant-mass distributions show enhancements near thre…

PhysicsNuclear and High Energy PhysicsParticle physicsMeson010308 nuclear & particles physicsElectron–positron annihilationDalitz plotBaBar detector01 natural scienceslaw.inventionBaryonPionlaw0103 physical sciencesMass spectrumB meson010306 general physicsColliderPhysical Review D
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Observation of theχc2(2P)meson in the reactionγγ→DD¯atBABAR

2010

A search for the Z(3930) resonance in gamma gamma production of the DDbar system has been performed using a data sample corresponding to an integrated luminosity of 384 fb^-1 recorded by the BABAR experiment at the PEP-II asymmetric-energy electron-positron collider. The DDbar invariant mass distribution shows clear evidence of the Z(3930) state with a significance of 5.8 sigma. We determine mass and width values of (3926.7 +- 2.7 +- 1.1) MeV/c^2 and (21.3 +- 6.8 +- 3.6) MeV, respectively. A decay angular analysis provides evidence that the Z(3930) is a tensor state with positive parity and C-parity (J^PC = 2^++); therefore we identify the Z(3930) state as the chi_c2(2P) meson. The value of…

PhysicsNuclear and High Energy PhysicsParticle physicsMesonMass distribution010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaElectron–positron annihilationHadronBaBar experimentElementary particleAstrophysics::Cosmology and Extragalactic Astrophysics01 natural sciencesNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::ExperimentInvariant mass010306 general physicsPhysical Review D
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