Search for the lepton number violation decay $\ddot{I}•\to \ddot{I}{€}^{+}\ddot{I}{€}^{+}{e}^{-}{e}^{-}$ via $J/\ddot{I}ˆ\to \ddot{I}•\hat{I}\cdot$

Abstract

Using $(1.0087\pm 0.0044)\times 10^{10}$ $J/\ddot{I}ˆ$ events collected by the BESIII detector at the BEPCII collider, we search for the lepton number violation decay $\ddot{I}•\to \ddot{I}{€}^{+}\ddot{I}{€}^{+}{e}^{-}{e}^{-}$ via $J/\ddot{I}ˆ\to \ddot{I}•\hat{I}\cdot$. No signal is found and the upper limit on the branching fraction of $\ddot{I}•\to \ddot{I}{€}^{+}\ddot{I}{€}^{+}{e}^{-}{e}^{-}$ is set to be $9.7\times 10^{-6}$ at the 90\% confidence level.

10 pages, 5 figures