ISSN - 00319007, EISSN - 10797114, Physical Review Letters, 2014, vol. 112, p. -
Observation of a charged charmoniumlike structure in e+e- → (D* D ̄ *)±π at s =4.26GeV
© 2014 American Physical Society We study the process e+e-→(D*D̄*)±π at a center-of-mass energy of 4.26 GeV using a 827pb-1 data 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*D̄ *)± threshold in the π recoil mass spectrum, which we denote as the Zc±(4025). The measured mass and width of the structure are (4026.3±2.6±3.7)MeV/c2 and (24.8±5.6±7.7)MeV, respectively. Its production ratio σ(e+e-→Zc±(4025) π→(D*D̄*)±π)/σ(e+e- →(D*D̄*)±π) is determined to be 0.65±0.09±0.06. The first uncertainties are statistical and the second are systematic.