中国物理C（英文版）
中國物理C（英文版）
중국물리C（영문판）
CHINESE PHYSICS C--HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS
2010年
4期
421-426
,共6页
p(p)%threshold enhancement
The decay channel ψ′→π~+π~-J/ψ(J/ψ→γp(p)) is studied using a sample of 1.06 × 10~8 ψ′ events collected by the BESⅢ experiment at BEPCⅡ. A strong enhancement at threshold is observed in the p(p) invariant mass spectrum. The enhancement can be fitted with an S-wave Breit-Wigner resonance function with a resulting peak mass of M = 1861_(-13)~(+6) (stat)_(-26)~(+7) (syst) MeV/c~2 and a narrow width that is Γ＜ 38 MeV/c~2 at the 90% confidence level. These results are consistent with published BESⅡ results. These mass and width values do not match with well established mesons.
