Search for the FCNC charmonium decay $J/\ddot{I}ˆ\to D^0\hat{I}{¼}^{+}\hat{I}{¼}^{-}+\text{c.c.}$

Abstract

Based on a data sample of $(10087\pm 44)\times 10^6$ $J/\ddot{I}ˆ$ events taken with the BESIII detector, we search for the flavor-changing neutral current charmonium decay $J/\ddot{I}ˆ\to D^0\hat{I}{¼}^{+}\hat{I}{¼}^{-}+\text{c.c.}$. No significant signal above the background is observed, and the upper limit on its branching fraction is set to be $\mathcal{B}(J/\ddot{I}ˆ\to D^0\hat{I}{¼}^{+}\hat{I}{¼}^{-}+\text{c.c.})<1.1\times 10^{-7}$ at the 90% confidence level. This marks the first search for a flavor-changing neutral current charmonium decay involving muons in the final state.

20 pages, 4 figures