Observation ofηcdecay intoΣ+Σ¯−and

Abstract

Observation of η c decay into Σ +Σ− and Ξ −Ξ+ final states c Nankai University, Tianjin,300071,China d also at the PNPI, Gatchina, Russia e now at Nagoya University, Nagoya, Japan f Guangxi University,Nanning,530004,China Using a data sample of 2.25×10 8 J/ψ events collected with the BESIII detector, we present the first observation of the decays of ηc mesons to Σ +Σ− and Ξ −Ξ+ . The branching fractions are measured to be (2.11 ± 0.28stat. ± 0.18syst. ± 0.50PDG) × 10 −3 and (0.89 ± 0.16stat. ± 0.08syst. ± 0.21PDG) × 10 −3 for ηc → Σ +Σ− and Ξ −Ξ+ , respectively. These branching fractions provide important information on the helicity selection rule in charmonium-decay processes.

Enhancement near the p¯Λ threshold in the χc0→pWang1, Duan2, Wang3 et al. 2020Phys. Rev. D10160View full textAdd to dashboardCite

“…The hadronic decays of the charmonium states could be used to understand the mechanisms of the charmonium decays and provide a good place to search for the light baryons and mesons, since the charmonium states are the SU(3) singlets, and the final states could provide an isospin filter [1][2][3][4][5][6][7]. For instance, we have studied the reactions of χ c0 →ΣΣπ and χ c0 →ΛΣπ, which could be used to search for the baryon state Σð1430Þ with J P ¼ 1=2 − and to understand the two-pole structure of the Λð1405Þ resonance [8,9].…”

Observation ofψ(3686)→pp¯η′and improved measurement ofAblikim1, Ачасов2, Ahmed3 et al. 2019Phys. Rev. DSelf Cite9020View full textAdd to dashboardCite

“…The uncertainty associated with the kinematic fit is estimated by comparing the efficiencies with or without a helix parameter correction applied to simulated data [30]. Control samples J=ψ → pK −Λ þ c:c: and ψð3686Þ → K þ K − π þ π − [31] are used to obtain the correction to the track helix parameters. The uncertainties due to the kinematic fit are determined to be 1.9%, 2.4%, 1.7%, and 2.3%, for ψð3686Þ → ppη 0 with η 0 → γπ þ π − , and ψð3686Þ → ppη 0 with η 0 → ηπ þ π − , J=ψ → ppη 0 with η 0 → γπ þ π − , and J=ψ → ppη 0 with η 0 → ηπ þ π − , respectively.…”