Recent N Results From J/ψ Decays
نویسنده
چکیده
Based on 7.8 million J/ψ events collected at BEPC, the events for J/ψ → pp̄π and pp̄η have been selected and reconstructed. Clear peaks are observed around 1480 MeV in pπ(p̄π) invariant mass spectrum and near the threshold for η production in pη(p̄η) invariant mass spectrum. A partial wave analysis of J/ψ → pp̄η data has been performed. Two J = 1 2 − resonances are observed with mass and width (M, Γ) at (1540 −17, 178 +20 −22) MeV and (1648 −16, 150)MeV, and are considered to be the nucleon resonances S11(1535) and S11(1650) respectively.
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تاریخ انتشار 1999