Observation of the decay Lambda(0)(b) -> pK(-)mu(+)mu(-) and a search for CP violation
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Published version
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Type
Journal Article
Abstract
A search for CP violation in the decay Λb0 → pK−μ+μ− is presented. This decay is mediated by flavour-changing neutral-current transitions in the Standard Model and is potentially sensitive to new sources of CP violation. The study is based on a data sample of proton-proton collisions recorded with the LHCb experiment, corresponding to an integrated luminosity of 3 fb−1. The Λb0 → pK−μ+μ− decay is observed for the first time, and two observables that are sensitive to different manifestations of CP violation are measured, ΔACP≡ACP(Λ0b→pK−μ+μ−)−ACP(Λ0b→pK−J/ψ)ΔACP≡ACP(Λb0→pK−μ+μ−)−ACP(Λb0→pK−J/ψ) and aaTˆ-oddCPaCPT^-odd, where the latter is based on asymmetries in the angle between the μ+μ− and pK− decay planes.
These are measured to be
ΔACP=(−3.5±5.0(stat)±0.2(syst))×10−2,aTˆ-oddCP=(1.2±5.0(stat)±0.7(syst))×10−2,
ΔACP=(−3.5±5.0(stat)±0.2(syst))×10−2,aCPT^-odd=(1.2±5.0(stat)±0.7(syst))×10−2,
and no evidence for CP violation is found.
These are measured to be
ΔACP=(−3.5±5.0(stat)±0.2(syst))×10−2,aTˆ-oddCP=(1.2±5.0(stat)±0.7(syst))×10−2,
ΔACP=(−3.5±5.0(stat)±0.2(syst))×10−2,aCPT^-odd=(1.2±5.0(stat)±0.7(syst))×10−2,
and no evidence for CP violation is found.
Date Issued
2017-06-21
Date Acceptance
2017-03-25
Citation
Journal of High Energy Physics, 2017, 2017 (6)
ISSN
1029-8479
Publisher
Springer Verlag (Germany)
Journal / Book Title
Journal of High Energy Physics
Volume
2017
Issue
6
Copyright Statement
Open Access, Copyright CERN,
for the benefit of the LHCb Collaboration.
Article funded by SCOAP3
for the benefit of the LHCb Collaboration.
Article funded by SCOAP3
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Subjects
Science & Technology
Physical Sciences
Physics, Particles & Fields
Physics
B physics
CP violation
FCNC Interaction
Hadron-Hadron scattering (experiments)
BARYON ASYMMETRY
Publication Status
Published
Article Number
108