Measurement of the Born cross section for $e^{+}{e}^{-}\to \eta h_c$ at center-of-mass energies between 4.1 and 4.6\,GeV

Abstract

We measure the Born cross section for the reaction $e^{+}{e}^{-}\to \eta h_c$ from $\sqrt{s}=4.129$ to $4.600$~GeV using data sets collected by the BESIII detector running at the BEPCII collider. A resonant structure in the cross section line shape near 4.200~GeV is observed with a statistical significance of 7$\sigma$. The parameters of this resonance are measured to be \MeasMass\ and \MeasWidth, where the first uncertainties are statistical and the second systematic.