Observation of Structures in the Processes e+e- ???c1 and ??c2

We present measurements of the Born cross sections for the processes e+e-???c1 and ??c2 at center-of-mass energies s from 4.308 to 4.951 GeV. The measurements are performed with data samples corresponding to an integrated luminosity of 11.0 fb-1 collected with the BESIII detector operating at the Beijing Electron Positron Collider storage ring. Assuming the e+e-???c2 signals come from a single resonance, the mass and width are determined to be M=(4413.6±9.0±0.8) MeV/c2 and ?=(110.5±15.0±2.9) MeV, respectively, which is consistent with the parameters of the well-established resonance ?(4415). In addition, we also use one single resonance to describe the e+e-???c1 line shape and determine the mass and width to be M=(4544.2±18.7±1.7) MeV/c2 and ?=(116.1±33.5±1.7) MeV, respectively. The structure of this line shape, observed for the first time, requires further understanding. © 2024 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.