Cross Section Measurement of from ~GeV to 4.6984~GeV
arXiv:2107.09210 · doi:10.1103/PhysRevD.104.052012
Abstract
Using data samples with a total integrated luminosity of collected by the BESIII detector operating at the BEPCII collider, the cross section of the process is measured at center-of-mass energies between 4.0076 and 4.6984 GeV. The measured cross section is consistent with previous results, but with much improved precision. A fit to the measured energy-dependent cross section, which includes three Breit-Wigner functions and a non-resonant contribution, confirms the existence of the charmonium-like states , , and . This is the first observation of the at the BESIII experiment.
12 pages, 5 figures