0000000000118456

AUTHOR

Liu D

showing 3 related works from this author

First Measurement of the Absolute Branching Fraction of Λ→pμ−ν¯μ

2021

The absolute branching fraction of Λ→pμ−ν¯μ is reported for the first time based on an e+e− annihilation sample of 10×109 J/ψ events collected with the BESIII detector at s=3.097 GeV. The branching fraction is determined to be B(Λ→pμ−ν¯μ)=[1.48±0.21(stat)±0.08(syst)]×10−4, which is improved by about 30% in precision over the previous indirect measurements. Combining this result with the world average of B(Λ→pe−ν¯e), we obtain the ratio {[Γ(Λ→pμ−ν¯μ)]/[Γ(Λ→pe−ν¯e)]} to be 0.178±0.028, which agrees with the standard model prediction assuming lepton flavor universality. The asymmetry of the branching fractions of Λ→pμ−ν¯μ and Λ¯→p¯μ+νμ is also determined, and no evidence for CP violation is fo…

PhysicsMeasurementAnnihilationBranching010308 nuclear & particles physicsBranching fractionmedia_common.quotation_subjectGeneral Physics and AstronomyAbsoluteTime based01 natural sciencesAsymmetryNOStandard ModelSubatomär fysikSubatomic Physics0103 physical sciencesCP violationAtomic physics010306 general physicsLeptonmedia_commonPhysical Review Letters
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Complete Measurement of the Λ Electromagnetic Form Factors.

2019

The exclusive process e+e−→ΛΛ¯, with Λ→pπ− and Λ¯→p¯π+, has been studied at s=2.396 GeV for measurement of the timelike Λ electric and magnetic form factors, GE and GM. A data sample, corresponding to an integrated luminosity of 66.9 pb−1, was collected with the BESIII detector for this purpose. A multidimensional analysis with a complete decomposition of the spin structure of the reaction enables a determination of the modulus of the ratio R=|GE/GM| and, for the first time for any baryon, the relative phase ΔΦ=ΦE−ΦM. The resulting values are R=0.96±0.14(stat)±0.02(syst) and ΔΦ=37°±12°(stat)±6°(syst), respectively. These are obtained using the recently established and most precise value of …

Multi-dimensional analysisElectron–positron annihilationRelative phaseHadronAnalytical chemistryGeneral Physics and AstronomyHadronsOBSERVABLESLambdaBaryon01 natural sciencesArticleNOHigh Energy Physics - ExperimentSubatomär fysikGermanium compoundsElectromagnetic form factorsSubatomic Physics0103 physical sciencesMagnetic form factorTwo-photon exchangePiddc:530010306 general physicsAsymmetry parameterProton Scattering; Nucleons; HydrogenPhysicsIntegrated luminosityDecompositionPhysicsHigh Energy Physics::PhenomenologyApproximation theoryPhysics multidisciplinaryPhotonHigh Energy Physics - Experiment; High Energy Physics - ExperimentBaryonLuminanceSpin structuresHigh Energy Physics::ExperimentMagnetic form factorMulti dimensional analysisBar (unit)Physical review letters
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Adiabatic versus Non-Adiabatic Electron Transfer at 2D Electrode Materials

2021

<div><div><div><p>Outer-sphere electron transfer (OS-ET) is a cornerstone elementary electrochemical reaction, yet microscopic understanding is largely based on idealized theories, developed in isolation from experiments that themselves are often close to the kinetic (diffusion) limit. Focusing on graphene as-grown on a copper substrate as a model 2D material/metal-supported electrode system, this study resolves the key electronic interactions in OS-ET, and identifies the role of graphene in modulating the electronic properties of the electrode/electrolyte interface. An integrated experimental-theoretical approach combining co-located multi-microscopy, centered on sc…

Electron transferMaterials scienceGraphenelawChemical physicsBilayerMonolayerOuter sphere electron transferDensity functional theoryBilayer graphenelaw.inventionElectrochemical cell
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