Abstract
The decays Λ 0b → ψ(2S)pK− and Λ 0b → 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 Λ 0b → J/ψpK− are measured to be
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
where the uncertainties are statistical and systematic.
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ArXiv ePrint: 1603.06961
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The LHCb collaboration., Aaij, R., Abellán Beteta, C. et al. Observation of Λ 0b → ψ(2S)pK− and Λ 0b → J/ψπ + π −pK− decays and a measurement of the Λ 0b baryon mass. J. High Energ. Phys. 2016, 132 (2016). https://doi.org/10.1007/JHEP05(2016)132
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DOI: https://doi.org/10.1007/JHEP05(2016)132