Evidence for the decay mode X(3872) → ψ(2S)γ in B +→ X(3872)K +decays is found with a sig-nificance of 4.4 standard deviations. The analysis is based on adata sample of proton-proton collisions, corresponding to an integrated luminosity of 3 fb the X(3872), collected with the LHCb detector, at centre-of-mass energies of 7 and 8 TeV. The ratio of the branching fraction of the X(3872) → ψ(2S)γ decay to that of the X(3872) → J/ψγ decay is measured to be B(X(3872) → ψ(2S)γ)/B(X(3872) → J/ψγ) = 2.46 ± 0.64 ± 0.29, where the first uncertainty is statistical and the second is systematic. The measured value does not support a pure DD* molecular interpretation of the X(3872)state.
Bibliographical noteFunding Information:
We express our gratitude to our colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at the LHCb institutes. We acknowledge support from CERN and from the national agencies: CAPES , CNPq , FAPERJ and FINEP (Brazil); NSFC (China); CNRS/IN2P3 and Region Auvergne (France); BMBF , DFG , HGF and MPG (Germany); SFI (Ireland); INFN (Italy); FOM and NWO (The Netherlands); SCSR (Poland); MEN/IFA (Romania); MinES , Rosatom , RFBR and NRC “ Kurchatov Institute ” (Russia); MinECo , XuntaGal and GENCAT (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC and the Royal Society (United Kingdom); NSF (USA). We also acknowledge the support received from EPLANET , Marie Curie Actions and the ERC under FP7. The Tier1 computing centres are supported by IN2P3 (France), KIT and BMBF (Germany), INFN (Italy), NWO and SURF (The Netherlands), PIC (Spain), GridPP (United Kingdom). We are indebted to the communities behind the multiple open source software packages on which we depend. We are also thankful for the computing resources and the access to software R&D tools provided by Yandex LLC (Russia).
© 2014 CERN for the benefit of the LHCb Collaboration.
Copyright 2019 Elsevier B.V., All rights reserved.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics