Branching Ratios of J/ψ→π03(π+π-)
- Received Date: 2001-05-28
- Accepted Date: 1900-01-01
- Available Online: 2002-01-05
Abstract: The decay mode of J/ψ→π03(π+π-) was studied very little before. There are no informations except branching ratios for this channel in PDG book which based on less than 0.2×106J/ψ events of MARKⅠ. Now, BESⅠ has a data sample of 7.8×106J/ψ events, we can make more accurate results than MARKⅠ. Total of 3290±43 J/ψ→π03(π+π-) events including 1275±86 J/ψ→ω2(π+π-) events are selected. J/ψ→π03(π+π-) and J/ψ→ω2(π+π-) events have been generated with MC simulition for calculating events selection efficiency. BESⅠ result is: Br(J/ψ→π03(π+π-))=(2.52±0.06±0.43)% and Br(J/ψ→π03(π+π-))=(1.31±0.09±0.21)%. Meanwhile, we studied the invariant mass of 4π and ωππ to find interesting signals. It seems that there is a peak at about 1.74GeV in the invarianat mass spectrum of 4π, and a enhancement was also found at about 1.9GeV in the invariant mass spectrum of ωππ. It is not clear whether they are from resonances or background. Therefore, more work in detail is still going on.