Ablikim, Medina N.Achasov, M. N.Adlarson, PatrikAlbrecht, MalteAliberti, Riccardo2022-11-132022-11-132022Ablikim, M., Achasov, M. N., Adlarson, P., Albrecht, M., Aliberti, R., Amoroso, A., ... & Jiang, X. S. (2022). Observation of η c (2 S)→ 3 (π+ π−) and measurements of χ c J→ 3 (π+ π−) in ψ (3686) radiative transitions. Physical Review D, 106(3), 032014.2470-0010https://doi.org/10.1103/PhysRevD.106.032014https://hdl.handle.net/20.500.12713/3364The hadronic decay ?c(2S)?3(?+?-) is observed with a statistical significance of 9.3 standard deviations using (448.1±2.9)×106 ?(3686) events collected by the BESIII detector at the BEPCII collider. The measured mass and width of ?c(2S) are (3643.4±2.3 (stat)±4.4 (syst)) MeV/c2 and (19.8±3.9 (stat)±3.1 (syst)) MeV, respectively, which are consistent with the world average values within two standard deviations. The product branching fraction B[?(3686)???c(2S)]×B[?c(2S)?3(?+?-)] is measured to be (9.2±1.0 (stat)±1.2 (syst))×10-6. Using B[?(3686)???c(2S)]=(7.0-2.5+3.4)×10-4, we obtain B[?c(2S)?3(?+?-)]=(1.31±0.15 (stat)±0.17 (syst) (+0.64-0.47) (extr))×10-2, where the third uncertainty is from B[?(3686)???c(2S)]. We also measure the ?cJ?3(?+?-) (J=0, 1, 2) decays via ?????cJ transitions. The branching fractions are B[?c0?3(?+?-)]=(2.080±0.006 (stat)±0.068 (syst))×10-2, B[?c1?3(?+?-)]=(1.092±0.004 (stat)±0.035 (syst))×10-2, and B[?c2?3(?+?-)]=(1.565±0.005 (stat)±0.048 (syst))×10-2. © 2022 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.eninfo:eu-repo/semantics/openAccessArticle1063WOS:0008895559000012-s2.0-85136876466Q110.1103/PhysRevD.106.032014Q1