Observation of $e^{+}{e}^{-}\to {\eta }^{\prime }J/\psi$ at center-of-mass energies between 4.189 and 4.600 GeV

M. Ablikim, M. N. Achasov, S. Ahmed +428

The process $e^{+}{e}^{-}\to {\eta }^{\prime }J/\psi$ is observed for the first time with a statistical significance of $8.6\sigma$ at center-of-mass energy $\sqrt{s}=4.226$ GeV and $7.3\sigma$ at $\…