A search for charge-parity (CP) violation in D0 → K− K+ and D0 → π− π+ decays is reported, using pp 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)+ → D0 π+ decays or from the charge of the muon in anti-B → D0 μ− anti-ν_μ X decays. The difference between the CP asymmetries in D0 → K− K+ and D0 → π− π+ decays is measured to be ΔA_CP = [−18.2 ± 3.2(stat) ± 0.9(syst)] × 10^−4 for π-tagged and ΔA_CP = [−9 ± 8(stat) ± 5(syst)] × 10^−4 for μ-tagged D0 mesons. Combining these with previous LHCb results leads to ΔA_CP = (−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 CP violation in the decay of charm hadrons.

Aaij, R., Abellán Beteta, C., Adeva, B., Adinolfi, M., Aidala, C., Ajaltouni, Z., et al. (2019). Observation of CP Violation in Charm Decays. PHYSICAL REVIEW LETTERS, 122(21), 1-12 [10.1103/PhysRevLett.122.211803].

Observation of CP Violation in Charm Decays

Betti, F.;Capriotti, L.;Carbone, A.;Ferrari, F.;Galli, D.;Patrignani, C.;Perazzini, S.;Pisani, F.;Vagnoni, V.;Zucchelli, S.
2019

Abstract

A search for charge-parity (CP) violation in D0 → K− K+ and D0 → π− π+ decays is reported, using pp 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)+ → D0 π+ decays or from the charge of the muon in anti-B → D0 μ− anti-ν_μ X decays. The difference between the CP asymmetries in D0 → K− K+ and D0 → π− π+ decays is measured to be ΔA_CP = [−18.2 ± 3.2(stat) ± 0.9(syst)] × 10^−4 for π-tagged and ΔA_CP = [−9 ± 8(stat) ± 5(syst)] × 10^−4 for μ-tagged D0 mesons. Combining these with previous LHCb results leads to ΔA_CP = (−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 CP violation in the decay of charm hadrons.
2019
Aaij, R., Abellán Beteta, C., Adeva, B., Adinolfi, M., Aidala, C., Ajaltouni, Z., et al. (2019). Observation of CP Violation in Charm Decays. PHYSICAL REVIEW LETTERS, 122(21), 1-12 [10.1103/PhysRevLett.122.211803].
Aaij, R.; Abellán Beteta, C.; Adeva, B.; Adinolfi, M.; Aidala, C.A.; Ajaltouni, Z.; Akar, S.; Albicocco, P.; Albrecht, J.; Alessio, F.; Alexander, M.;...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/688260
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