TY - JOUR AU - LHCb Collaboration (Aaij, R. et al AU - Jaimes Elles, S. J. AU - Jashal, B. K. AU - Martinez-Vidal, F. AU - Oyanguren, A. AU - Rebollo De Miguel, M. AU - Remon Alepuz, C. AU - Ruiz Vidal, J. AU - Sanderswood, I. PY - 2023 DA - 2023// TI - Observation of a Resonant Structure near the Ds+Ds- Threshold in the B+ -> Ds+Ds- K+ Decay T2 - Phys. Rev. Lett. JO - Physical Review Letters SP - 071901 EP - 12pp VL - 131 IS - 7 PB - Amer Physical Soc AB - An amplitude analysis of the B thorn & RARR; D thorn s D-s K thorn decay is carried out to study for the first time its intermediate resonant contributions, using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. A near-threshold peaking structure, referred to as X(3960), is observed in the D thorn s D-s invariant-mass spectrum with significance greater than 12 standard deviations. The mass, width, and the quantum numbers of the structure are measured to be 3956 1 5 1 10 MeV, 43 1 13 1 8 MeV, and JPC = 0 thorn thorn , respectively, where the first uncertainties are statistical and the second systematic. The properties of the new structure are consistent with recent theoretical predictions for a state composed of cc over bar ss over bar quarks. Evidence for an additional structure is found around 4140 MeV in the D thorn s D-s invariant mass, which might be caused either by a new resonance with the 0 thorn thorn assignment or by a J=& psi;& phi; & LRARR; D thorn s D-s coupled-channel effect. SN - 0031-9007 UR - https://arxiv.org/abs/2210.15153 UR - https://doi.org/10.1103/PhysRevLett.131.071901 DO - 10.1103/PhysRevLett.131.071901 LA - English N1 - WOS:001066381600001 ID - LHCbCollaborationAaij_etal2023 ER -