Observation of a resonance X(1835) in J/ψ--> γπ^+ π^- η^{\prime}

BES Collaboration, M. Ablikim

The decay channel J/ψ--> γπ^+ π^- η^{\prime} is analyzed using a sample of 5.8\times 10^7 Jψevents collected with the BESII detector. A resonance, the X(1835), is observed in the π…