Ablikim, Medina N.Achasov, M. N.Adlarson, PatrikAlbrecht, MalteAliberti, Riccardo2022-11-082022-11-082022Ablikim, M., Achasov, M. N., Adlarson, P., Albrecht, M., Aliberti, R., Amoroso, A., . . . BESIII Collaboration. (2022). Observation of resonance structures in e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) and mass measurement of ψ_{2}(3823). Physical Review Letters, 129(10), 102003. doi:10.1103/PhysRevLett.129.102003https://doi.org/10.1103/PhysRevLett.129.102003https://hdl.handle.net/20.500.12713/3282Using a data sample corresponding to an integrated luminosity of 11.3??fb^{-1} collected at center-of-mass energies from 4.23 to 4.70 GeV with the BESIII detector, we measure the product of the e^{+}e^{-}??^{+}?^{-}?_{2}(3823) cross section and the branching fraction B[?_{2}(3823)???_{c1}]. For the first time, resonance structure is observed in the cross section line shape of e^{+}e^{-}??^{+}?^{-}?_{2}(3823) with significances exceeding 5?. A fit to data with two coherent Breit-Wigner resonances modeling the sqrt[s]-dependent cross section yields M(R_{1})=4406.9±17.2±4.5??MeV/c^{2}, ?(R_{1})=128.1±37.2±2.3??MeV, and M(R_{2})=4647.9±8.6±0.8??MeV/c^{2}, ?(R_{2})=33.1±18.6±4.1??MeV. Though weakly disfavored by the data, a single resonance with M(R)=4417.5±26.2±3.5??MeV/c^{2}, ?(R)=245±48±13??MeV is also possible to interpret data. This observation deepens our understanding of the nature of the vector charmoniumlike states. The mass of the ?_{2}(3823) state is measured as (3823.12±0.43±0.13)??MeV/c^{2}, which is the most precise measurement to date.eninfo:eu-repo/semantics/closedAccessArticle12910WOS:000890664900002Q110.1103/PhysRevLett.129.102003N/A