@article{8446b51faffc4108ab10790974280035,
title = "Observation of ψ (3686) →e+e-χcJ and χcJ →e+e-J /ψ",
abstract = "Using 4.479×108 ψ(3686) events collected with the BESIII detector, we search for the decays ψ(3686)→e+e-χcJ and χcJ→e+e-J/ψ, where J=0, 1, 2. The decays ψ(3686)→e+e-χcJ and χcJ→e+e-J/ψ are observed for the first time. The measured branching fractions are B(ψ(3686)→e+e-χcJ)=(11.7±2.5±1.0)×10-4, (8.6±0.3±0.6)×10-4, (6.9±0.5±0.6)×10-4 for J=0, 1, 2, and B(χcJ→e+e-J/ψ)=(1.51±0.30±0.13)×10-4, (3.73±0.09±0.25)×10-3, (2.48±0.08±0.16)×10-3 for J=0, 1, 2, respectively. The ratios of the branching fractions B(ψ(3686)→e+e-χcJ)/B(ψ(3686)→γχcJ) and B(χcJ→e+e-J/ψ)/B(χcJ→γJ/ψ) are also reported. Also, the α values of helicity angular distributions of the e+e- pair are determined for ψ(3686)→e+e-χc1,2 and χc1,2→e+e-J/ψ.",
author = "{(BESIII Collaboration)} and M. Ablikim and Achasov, {M. N.} and Ai, {X. C.} and O. Albayrak and M. Albrecht and Ambrose, {D. J.} and A. Amoroso and An, {F. F.} and Q. An and Bai, {J. Z.} and {Baldini Ferroli}, R. and Y. Ban and Bennett, {D. W.} and Bennett, {J. V.} and M. Bertani and D. Bettoni and Bian, {J. M.} and F. Bianchi and E. Boger and I. Boyko and Briere, {R. A.} and H. Cai and X. Cai and O. Cakir and A. Calcaterra and Cao, {G. F.} and Cetin, {S. A.} and Chang, {J. F.} and G. Chelkov and G. Chen and Chen, {H. S.} and Chen, {H. Y.} and Chen, {J. C.} and Chen, {M. L.} and S. Chen and Chen, {S. J.} and X. Chen and Chen, {X. R.} and Chen, {Y. B.} and Cheng, {H. P.} and Chu, {X. K.} and G. Cibinetto and Dai, {H. L.} and Dai, {J. P.} and A. Dbeyssi and D. Dedovich and Deng, {Z. Y.} and A. Denig and I. Denysenko and M. Destefanis",
note = "Publisher Copyright: {\textcopyright} 2017 American Physical Society.",
year = "2017",
month = may,
day = "30",
doi = "10.1103/PhysRevLett.118.221802",
language = "English",
volume = "118",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "22",
}