Observation of Λ0b → ψ(2S)pK− and Λ0b → J/ψπ + π −pK− decays and a measurement of the Λ0b baryon mass

LHCb CollaborationAdeva Andany, BernardoBorsato, MartinoDosil Suárez, ÁlvaroFernández Albor, Víctor ManuelGallas Torreira, Abraham AntonioGarcía Pardiñas, JuliánHernando Morata, José ÁngelLemos Cid, EdgarLucio Martínez, MiriamMartínez Santos, DiegoPlo Casasus, MáximoPrisciandaro, JessicaRamos Pernas, MiguelRomero Vidal, AntonioSaborido Silva, Juan JoséSanmartín Sedes, BraisSantamarina Ríos, CibránVázquez Regueiro, PabloVázquez Sierra, CarlosVieites Díaz, María2020-05-202020-05-202016Aaij, R., Abellán Beteta, C., Adeva, B. et al. Observation of Λ0b → ψ(2S)pK− and Λ0b → J/ψπ + π −pK− decays and a measurement of the Λ0b baryon mass. J. High Energ. Phys. 2016, 132 (2016). https://doi.org/10.1007/JHEP05(2016)1321029-8479http://hdl.handle.net/10347/22473The decays Λ0b → ψ(2S)pK− and Λ0b → J/ψπ + π −pK− are observed in a data sample corresponding to an integrated luminosity of 3 fb−1, collected in proton-proton collisions at 7 and 8 TeV centre-of-mass energies by the LHCb detector. The ψ(2S) mesons are reconstructed through the decay modes ψ(2S) → μ+μ− and ψ(2S) → J/ψπ + π −. The branching fractions relative to that of Λ0b → J/ψpK− are measured to be B(Λ0b→ψ(2S)pK−)B(Λ0b→J/ψpK−)=(20.70±0.76±0.46±0.37)×10−2, where the first uncertainties are statistical, the second are systematic and the third is related to the knowledge of J/ψ and ψ(2S) branching fractions. The mass of the Λ 0b baryon is measured to be M(Λ0b)=5619.65±0.17±0.17 MeV/c2, where the uncertainties are statistical and systematic.eng© CERN, for the benefit of the LHCb Collaboration. Article funded by SCOAP3. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0), which permits use, duplication, adaptation, distribution, and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.https://creativecommons.org/licenses/by/4.0B physicsFlavor physicsHadron-Hadron scattering (experiments)Particle and resonance productionSpectroscopyObservation of Λ0b → ψ(2S)pK− and Λ0b → J/ψπ + π −pK− decays and a measurement of the Λ0b baryon massjournal article10.1007/JHEP05(2016)132open access