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 language | English |
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Article number | 103 |
Number of pages | 19 |
Journal | Journal of High Energy Physics |
Volume | 1407 |
Issue number | 7 |
Early online date | 22 Jul 2014 |
DOIs | |
Publication status | E-pub ahead of print - 22 Jul 2014 |
Keywords / Materials (for Non-textual outputs)
- B physics
- CP violation
- Branching fraction
- Flavor physics
- Hadron-Hadron Scattering
- TOOL