Study of $J/\ddot{I}ˆ\to \ddot{I}‰p\bar{p}$ at BESIII

Abstract

The decay $J/\ddot{I}ˆ\to \ddot{I}‰p\bar{p}$ has been studied, using $225.3\times 10^6$ $J/\ddot{I}ˆ$ events accumulated at BESIII. No significant enhancement near the $p\bar{p}$ invariant-mass threshold (denoted as $X(p\bar{p})$) is observed. The upper limit of the branching fraction $\mathcal{B}(J/\ddot{I}ˆ\to \ddot{I}‰X(p\bar{p})\to \ddot{I}‰p\bar{p})$ is determined to be $3.9\times 10^{-6}$ at the 95% confidence level. The branching fraction of $J/\ddot{I}ˆ\to \ddot{I}‰p\bar{p}$ is measured to be $\mathcal{B}(J/\ddot{I}ˆ\to \ddot{I}‰p\bar{p})=(9.0\pm 0.2(\text{stat.})\pm 0.9(\text{syst.}))\times 10^{-4}$.

8 pages, 4 figures