Observation of ψ(3770)→ηJ/ψ

2022/12/23 by BESIII Collaboration
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions

paper · pdf · doi:10.48550/arxiv.2212.12165

openalex publication_date 2022/12/23 · openalex created_date 2023/01/04 · openalex updated_date 2026/07/28

Abstract

The Born cross section of the process e⁺e^-→ηJ/ψ at a center-of-mass energy √(s)=3.773 ~GeV is measured to be (8.89±0.88±0.42)~pb, using a data sample collected with the BESIII detector operating at the BEPCII storage ring. The decay ψ(3770)→ηJ/ψ is observed for the first time with a statistical significance of 7.4σ. From a fit to the dressed cross-section line-shape of e⁺e^-→ηJ/ψ from √(s)=3.773 to 4.600~GeV we obtain the branching fraction of the decay ψ(3770)→ ηJ/ψ to be (11.6±6.1±1.0)× 10^-4 when the ψ(3770) decay amplitude is added coherently to the other contributions, and (7.9±1.0±0.7)× 10^-4 when it is added incoherently. Here the first uncertainties are statistical and the second are systematic.

Related

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