Cross section measurements of $e^{+}{e}^{-}\to \ddot{I}‰\ddot{I}{‡}_{c0}$ from $\sqrt{s}=$4.178 to 4.278 GeV

Abstract

The cross section of the process $e^{+}{e}^{-}\to \ddot{I}‰\ddot{I}{‡}_{c0}$ is measured at center-of-mass energies from $\sqrt{s}=$ 4.178 to 4.278 GeV using a data sample of 7 fb${}^{-1}$ collected with the BESIII detector operating at the BEPCII storage ring. The dependence of the cross section on $\sqrt{s}$ shows a resonant structure with mass of $(4218.5\pm 1.6(\text{stat.})\pm 4.0(\text{syst.}))$ MeV/$c^2$ and width of $(28.2\pm 3.9(\text{stat.})\pm 1.6(\text{syst.}))$ MeV, respectively. This observation confirms and improves upon the result of a previous study. The angular distribution of the $e^{+}{e}^{-}\to \ddot{I}‰\ddot{I}{‡}_{c0}$ process is extracted for the first time.

8 pages, 4 figures, 3 tables