Unexpected large relative strong phase and search for isospin breaking and $CP$ asymmetries in $J/ψ\to K^*(892)\bar K

BESIII Collaboration, M. Ablikim, M. N. Achasov +766

Using a direct scan of 26 energy points near the $J/\ddot{I}ˆ$ resonance, we perform the first measurement of the relative phase $\ddot{I}{•}_{{\hat{I}}^3,3g}$ between the strong and electromagnetic ampli…