BES上J／ψ→γπ^0π^0的实验研究

Study of J／ψ、γπ~0π~0 at BES

基于北京谱仪收集的7．0×10~6有中性触发的J／ψ事例，分析了J／ψ→φπ~0π~0衰变道．除了在π~0π~0不变质量谱中看到了众所周知的f_2（1270）外，还证实了f_J（1710）和ξ（2230）的存在，同时给出了它们的质量以及相应的衰变分支比．

The decay J／ψ→φπ0π0 is studied with 7．0 × 10~6 produced J／ψ events collected by the Bening Spectrometer（BES） with the tugger mode senseuve to both chmped and neutral final state at the Bening Electron－Positron Collider（BEPC）， The evidences for the existence of fJ（1710） and E（2230） in this channel are presented， and the corresponding masses as wen asthe product branching ratios are obtained.