Triangle singularity in the $J/\ddot{I}ˆ\to \ddot{I}•\ddot{I}{€}^{+}{a}_0^{-}(\ddot{I}{€}^{-}\hat{I}\cdot ),\ddot{I}•\ddot{I}{€}^{-}{a}_0^{+}(\ddot{I}{€}^{+}\hat{I}\cdot )$ decays

C. W. Xiao, J. M. Dias, L. R. Dai +2

We study the $J/\ddot{I}ˆ\to \ddot{I}•\ddot{I}{€}^{+}{a}_0(980{)}^{-}(a_0^{-}\to \ddot{I}{€}^{-}\hat{I}\cdot )$ decay, evaluating the double mass distribution in terms of the $\ddot{I}{€}^{-}\hat{I}\cdot$ and $\ddot{I}{€}^{+}{a}_0^{-}$ invariant masses. We show tha…