The numbers of ψ(3686) events accumulated by the BESIII detector for the data taken during 2009 and 2012 are determined to be (107.0±0.8)×10 6 and (341.1±2.1)×10 6 , respectively, by counting inclusive hadronic events, where the uncertainties are systematic and the statistical uncertainties are negligible. The number of events for the sample taken in 2009 is consistent with that of the previous measurement. The total number of ψ(3686) events for the two data taking periods is (448.1±2.9)×10 6 .
Based on 106×10(6)ψ(3686) events collected with the BESIII detector at the BEPCII facility, a partial wave analysis of ψ(3686)→ppπ0 is performed. The branching fraction of this channel has been determined to be B(ψ(3686)→ppπ0)=(1.65±0.03±0.15)×10(-4). In this decay, 7 N* intermediate resonances are observed. Among these, two new resonances, N(2300) and N(2570) are significant, one 1/2+ resonance with a mass of 2300(-30-0)(+40+109) MeV/c2 and width of 340(-30-58)(+30+110) MeV/c2, and one 5/2- resonance with a mass of 2570(-10-10)(+19+34) MeV/c2 and width of 250(-24-21)(+14+69) MeV/c2. For the remaining 5 N* intermediate resonances [N(1440), N(1520), N(1535), N(1650) and N(1720)], the analysis yields mass and width values that are consistent with those from established resonances.
Observation of J/ψ → ppa 0 (980) at BESIII 8 J/ψ events collected with the BESIII detector at the BEPCII storage rings, we observe for the first time the process J/ψ → ppa0(980), a0(980) → π 0 η with a significance of 6.5σ (3.2σ including systematic uncertainties). The product branching fraction of J/ψ → ppa0(980) → ppπ 0 η is measured to be (6.8 ± 1.2 ± 1.3) × 10 −5 , where the first error is statistical and the second is systematic. This measurement provides information on the a0 production near threshold coupling to pp and improves the understanding of the dynamics of J/ψ decays to four body processes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.