2026-04-17T16:16:09Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1621572025-12-05T16:38:04Zcom_2072_1057col_2072_478823col_2072_478904col_2072_478917

Observation of the Λb0→χc1 (3872) pK− decay LHCb Collaboration Alfonso Albero, Alejandro Calvo Gómez, Míriam Camboni, Alessandro Coquereau, Samuel Garrido Beltrán, Lluís Gascón Fora, David Gironella Gironell, Pere Graciani Díaz, Ricardo Graugés Pous, Eugeni Vilasis-Cardona, Xavier Hadrons Col·lisions (Física) Experiments Hadrons Collisions (Physics) Experiments Using proton-proton collision data, collected with the LHCb detector and corresponding to 1.0, 2.0 and 1.9 fb−1 of integrated luminosity at the centre-of-mass energies of 7, 8, and 13 TeV, respectively, the decay Λ0 b → χc1(3872)pK− with χc1(3872) → J/ψ π+π − is observed for the first time. The significance of the observed signal is in excess of seven standard deviations. It is found that (58 ± 15)% of the decays proceed via the two-body intermediate state χc1(3872)Λ(1520). The branching fraction with respect to that of the Λ0 b → ψ(2S)pK− decay mode, where the ψ(2S) meson is reconstructed in the J/ψ π+π − final state, is measured to be: B(Λ0b → χc1(3872)pK−)B(Λ0b → ψ(2S)pK−)×B(χc1(3872) → J/ψ π+π−)B(ψ(2S) → J/ψ π+π−)= (5.4 ± 1.1 ± 0.2) × 10−2, where the first uncertainty is statistical and the second is systematic 2020-05-24T16:20:01Z 2020-05-24T16:20:01Z 2019-09-03 2020-05-24T16:20:02Z info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 1126-6708 https://hdl.handle.net/2445/162157 696336 eng Reproducció del document publicat a: https://doi.org/10.1007/JHEP09(2019)028 Journal of High Energy Physics, 2019, p. 28 https://doi.org/10.1007/JHEP09(2019)028 cc-by (c) LHCb Collaboration et al., 2019 http://creativecommons.org/licenses/by/3.0/es info:eu-repo/semantics/openAccess 19 p. application/pdf Springer Verlag Articles publicats en revistes (Física Quàntica i Astrofísica)