Near-threshold D(Formula presented.) spectroscopy and observation of a new charmonium state

Academic Article


  • © 2019, The Author(s). Using proton-proton collision data, corresponding to an integrated luminosity of 9 fb−1, collected with the LHCb detector between 2011 and 2018, a new narrow charmonium state, the X(3842) resonance, is observed in the decay modes X (3842) → DD¯ and X(3842) → D+D−. The mass and the natural width of this state are measured to be mX(3842)=3842.71±0.16±0.12MeV/c2,ΓX(3842)=2.79±0.51±0.35MeV, where the first uncertainty is statistical and the second is systematic. The observed mass and narrow natural width suggest the interpretation of the new state as the unobserved (spin-3 ψ3 13D3) charmonium state. In addition, prompt hadroproduction of the ψ(3770) and χ2(3930) states is observed for the first time, and the parameters of these states are measured to be mψ(3770)=3778.1±0.7±0.6MeV/c2,mχ2(3930)=3921.9±0.6±0.2MeV/c2,Γχ2(3930)=36.6±1.9±0.9MeV, where the first uncertainty is statistical and the second is systematic.[Figure not available: see fulltext.].
  • Digital Object Identifier (doi)

    Author List

  • Aaij R; Abellán Beteta C; Adeva B; Adinolfi M; Aidala CA; Ajaltouni Z; Akar S; Albicocco P; Albrecht J; Alessio F
  • Volume

  • 2019
  • Issue

  • 7