标题：Observation of a charged charmoniumlike structure in e+e-→ (D∗D∗)±π∓at √s =4.26 GeV
作者：Ablikim, M. ;Achasov, M.N. ;Albayrak, A.O. ;Ambrose, D.J. ;An, F.F. ;An, Q. ;Bai, J.Z. ;Baldini Ferroli, R. ;Ban, Y. ;Becker, J. ;Bennett, J.V. ;Berta 更多 作者机构：[Ablikim, M. ] PNPI, Gatchina; 188300, Russia;[Boger, E. ;Chelkov, G. ;Fuks, O. ] Moscow Institute of Physics and Technology, Moscow; 141700, Russia;[ 更多
来源：Physical Review Letters
摘要：We study the process e+e-→ (D∗D∗)±π∓at a center-of-mass energy of 4.26 GeV using a 827 pb-1data sample obtained with the BESIII detector at the Beijing Electron Positron Collider. Based on a partial reconstruction technique, the Born cross section is measured to be (137±9±15) pb. We observe a structure near the (D∗D∗)±threshold in the π∓recoil mass spectrum, which we denote as the Z± c (4025). The measured mass and width of the structure are (4026.3 ± 2.6 ± 3.7) MeV/c2and (24.8 ±5.6 ± 7.7) MeV, respectively. Its production ratio σ(e+e-→ Z±c(4025)π∓) → (D∗D∗)±π∓/σ(e+e-→ (D∗D∗)±π∓) is determined to be 0.65 ± 0.09 ± 0.06. The first uncertainties are statistical and the second are systematic.
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