Observation of the Λb0 → J/ψ pπ decay

Peter Clarke, Greig Cowan, Stephan Eisenhardt, Franz Muheim, Matthew Needham, Stephen Playfer, LHCb Collaboration

Research output: Contribution to journalArticlepeer-review

Abstract

The first observation of the Cabibbo-suppressed decay Λ0 b → J/ψpπ− is reported using a data sample of proton-proton collisions at 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb−1 . A prominent signal is observed and the branching fraction relative to the decay mode Λ0 b → J/ψpK− is determined to be B(Λ0 b → J/ψpπ−) B(Λ0 b → J/ψpK−) = 0.0824 ± 0.0025 (stat) ± 0.0042 (syst). A search for direct CP violation is performed. The difference in the CP asymmetries between these two decays is found to be ACP (Λ0 b → J/ψpπ−) − ACP (Λ0 b → J/ψpK−) = (+5.7 ± 2.4 (stat) ± 1.2 (syst))%, which is compatible with CP symmetry at the 2.2σ level.
Original languageEnglish
Article number103
Number of pages19
Journal Journal of High Energy Physics
Volume1407
Issue number7
Early online date22 Jul 2014
DOIs
Publication statusE-pub ahead of print - 22 Jul 2014

Keywords

  • B physics
  • CP violation
  • Branching fraction
  • Flavor physics
  • Hadron-Hadron Scattering
  • TOOL

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