Observation of CP Violation in Charm Decays
A search for charge-parity ( C P ) violation in D 0 → K − K + and D 0 → π − π + decays is reported, using p p collision data corresponding to an integrated luminosity of 5.9 fb − 1 collected at a center-of-mass energy of 13 TeV with the LHCb detector. The flavor of the charm meson is inferred fr...
| Authors: | , , , , , , , , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 2019 |
| Country: | España |
| Institution: | Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya) |
| Repository: | Recercat. Dipósit de la Recerca de Catalunya |
| OAI Identifier: | oai:recercat.cat:2445/170964 |
| Online Access: | https://hdl.handle.net/2445/170964 |
| Access Level: | Open access |
| Keyword: | Violació CP (Física nuclear) Hadrons CP violation (Nuclear physics) |
| Summary: | A search for charge-parity ( C P ) violation in D 0 → K − K + and D 0 → π − π + decays is reported, using p p collision data corresponding to an integrated luminosity of 5.9 fb − 1 collected at a center-of-mass energy of 13 TeV with the LHCb detector. The flavor of the charm meson is inferred from the charge of the pion in D ∗ ( 2010 ) + → D 0 π + decays or from the charge of the muon in ¯ B → D 0 μ − ¯ ν μ X decays. The difference between the C P asymmetries in D 0 → K − K + and D 0 → π − π + decays is measured to be Δ A C P = [ − 18.2 ± 3.2 ( stat ) ± 0.9 ( syst ) ] × 10 − 4 for π -tagged and Δ A C P = [ − 9 ± 8 ( stat ) ± 5 ( syst ) ] × 10 − 4 for μ -tagged D 0 mesons. Combining these with previous LHCb results leads to Δ A C P = ( − 15.4 ± 2.9 ) × 10 − 4 , where the uncertainty includes both statistical and systematic contributions. The measured value differs from zero by more than 5 standard deviations. This is the first observation of C P violation in the decay of charm hadrons. |
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