Observation of the Λ[0 over b] → J/ψ pπ[superscript −] decay
The first observation of the Cabibbo-suppressed decay Λ [0 over b] → J/ψpπ [superscript −] is reported using a data sample of proton-proton collisions at 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb[superscript −1]. A prominent signal is observed and the branching fraction relative...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
Springer-Verlag
2014
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| Online Access: | http://hdl.handle.net/1721.1/89434 https://orcid.org/0000-0001-8285-3346 https://orcid.org/0000-0002-4670-1334 https://orcid.org/0000-0001-5534-1732 |
| Summary: | The first observation of the Cabibbo-suppressed decay Λ [0 over b] → J/ψpπ [superscript −] is reported using a data sample of proton-proton collisions at 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb[superscript −1]. A prominent signal is observed and the branching fraction relative to the decay mode Λ [0 over b] → J/ψpK [superscript −] is determined to be B(Λ[0 over b] → J/ψpπ[superscript −])/B(Λ[0 over b] → J/ψpK[superscript −]) = 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 A[subscript CP](Λ[0 over b] → J/ψpπ[superscript −]) − A[subscript CP](Λ[0 over b] → J/ψpK[superscript −]) = (+5.7 ± 2.4 (stat) ± 1.2 (syst))%, which is compatible with CP symmetry at the 2.2σ level. |
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