Cross section measurement of $e^{+}{e}^{-}\to \hat{I}{\cdot }^{\prime }J/\ddot{I}ˆ$ from $\sqrt{s}=4.178$ to $4.600$ GeV

Abstract

The cross section of the process $e^{+}{e}^{-}\to \hat{I}{\cdot }^{\prime }J/\ddot{I}ˆ$ is measured at center-of-mass energies from $\sqrt{s}=$ 4.178 to 4.600 GeV using data samples corresponding to a total integrated luminosity of 11 fb${}^{-1}$ collected with the BESIII detector operating at the BEPCII storage ring. The dependence of the cross section on $\sqrt{s}$ shows an enhancement around $4.2$ GeV. While the shape of the cross section cannot be fully explained with a single $\ddot{I}ˆ(4160)$ or $\ddot{I}ˆ(4260)$ state, a coherent sum of the two states does provide a reasonable description of the data.