Study of the process $e^{+}{e}^{-}\to \ddot{I}•\hat{I}\cdot$ at center-of-mass energies between 2.00 and 3.08 GeV

Abstract

The process $e^{+}{e}^{-}\to \ddot{I}•\hat{I}\cdot$ is studied at 22 center-of-mass energy points ($\sqrt{s}$) between 2.00 and 3.08 GeV using 715 pb${}^{-1}$ of data collected with the BESIII detector. The measured Born cross section of $e^{+}{e}^{-}\to \ddot{I}•\hat{I}\cdot$ is found to be consistent with {\textsl{BABAR}} measurements, but with improved precision. A resonant structure around 2.175 GeV is observed with a significance of 6.9$\ddot{I}ƒ$ with mass ($2163.5\pm 6.2\pm 3.0$) MeV/$c^2$ and width ($31.1_{-11.6}^{+21.1}\pm 1.1$) MeV, where the first uncertainties are statistical and the second are systematic.