First energy scan measurement of $e^{+}{e}^{-}\to K^{+}{K}^{-}$ around the $\ddot{I}ˆ(2S)$ resonance

BESIII Collaboration, M. Ablikim, M. N. Achasov +684

We report the precise energy scan measurement of the cross section lineshape of $\ddot{I}ˆ(2S)\to K^{+}{K}^{-}$. The analysis is based on $e^{+}{e}^{-}$ collision data corresponding to an int…