LHCb Collaboration(Aaij, R. et al), Oyanguren, A., & Ruiz Valls, P. (2013). Search for CP violation in D+ -> phi pi(+) and D-s(+) -> K-S(0)pi(+) decays. J. High Energy Phys., 06(6), 112–20pp.
Abstract: A search for C P violation in D+ -> phi pi(+) decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb(-1) at a centre of mass energy of 7 TeV. The CP-violating asymmetry is measured to be (-0.04 +/- 0.14 +/- 0.14)% for candidates with K-K+ mass within 20 MeV/c(2) of the phi meson mass. A search for a CP-violating asymmetry that varies across the phi mass region of the D+ -> K-K+pi(+) Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D-s(+) -> K-S(0)pi(+) decay is measured to be (0.61 +/- 0.83 +/- 0.14)%.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2014). Search for CP violation using T-odd correlations in D-0 -> K+K-pi(+)pi(-) decays. J. High Energy Phys., 10(10), 005–21pp.
Abstract: A search for CP violation using T-odd correlations is performed using the four-body D-0 -> K+K-pi(+)pi(-) decay, selected from semileptonic B decays. The data sample corresponds to integrated luminosities of 1.0 fb(-1) and 2.0 fb(-1) recorded at the centre-of-mass energies of 7 TeV and 8 TeV, respectively. The CP-violating asymmetry alpha(T-odd)(CP) is measured to be (0.18 +/- 0.29 (stat) +/- 0.04 (syst))%. Searches for CP violation in different regions of phase space of the four-body decay, and as a function of the D-0 decay time, are also presented. No significant deviation from the CP conservation hypothesis is found.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2015). Measurement of indirect CP asymmetries in D-0 -> K-K+ and D-0 -> pi(-)pi(+) decays using semileptonic B decays. J. High Energy Phys., 04(4), 043–19pp.
Abstract: Time-dependent CP asymmetries in the decay rates of the singly Cabibbo-suppressed decays D-0 -> K-K+ and D-0 -> pi (-) pi(+) are measured in pp collision data corresponding to an integrated luminosity of 3.0 fb(-1) collected by the LHCb experiment. The D-0 mesons are produced in semileptonic b-hadron decays, where the charge of the accompanying muon is used to determine the initial state as D-0 or (D) over bar (0). The asymmetries in effective lifetimes between D-0 and (D) over bar (0) decays, which are sensitive to indirect CP violation, are determined to be A(Gamma) (K-K+) = (-0.134 +/- 0.077(-0.034)(+0.026))%, A(Gamma) (pi(-)pi(+)) = -0.092 +/- 0.145(-0.033)(+0.025))%, where the first uncertainties are statistical and the second systematic. This result is in agreement with previous measurements and with the hypothesis of no indirect CP violation in D (0) decays.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2014). Measurement of CP asymmetry in B-s(0) -> D-s(-/+) K-/+ decays. J. High Energy Phys., 11(11), 060–30pp.
Abstract: We report on measurements of the time-dependent CP violating observables in B-s(0) -> D-s(-/+) K--/+ decays using a dataset corresponding to 1.0 fb(-1) of pp collisions recorded with the LHCb detector. We find the CP violating observables C-f = 0.53 +/- 0.25 +/- 0.04, A(f)(Delta Gamma) = 0.37 +/- 0.42 +/- 0.20, A((f) over bar)(Delta Gamma) = 0.20 +/- 0.41 +/- 0.20, S-f = -1.09 +/- 0.33 +/- 0.08, S-(f) over bar = -0.36 +/- 0.34 +/- 0.08, where the uncertainties are statistical and systematic, respectively. Using these observables together with a recent measurement of the B-s(0) mixing phase -2 beta(s) leads to the first extraction of the CKM angle gamma from B-s(0) -> D-s(-/+) K--/+ decays, finding gamma = (115(-43)(+28))degrees modulo 180 degrees at 68% CL, where the error contains both statistical and systematic uncertainties.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2014). Measurement of the CKM angle gamma using B-+/- -> DK +/- with D -> K-S(0)pi(+)pi(-), (KSK+K-)-K-0 decays. J. High Energy Phys., 10(10), 097–52pp.
Abstract: A binned Dalitz plot analysis of B-+/- -> DK +/- decays, with D -> K-S(0) pi(+)pi(-) and D -> K0 S K + K -, is performed to measure the C P -violating observables x(+/-) and y(+/-), which are sensitive to the Cabibbo-Kobayashi-Maskawa angle gamma. The analysis exploits a sample of proton-proton collision data corresponding to 3.0 fb(-1) collected by the LHCb experiment. Measurements from CLEO-c of the variation of the strong-interaction phase of the D decay over the Dalitz plot are used as inputs. The values of the parameters are found to be x(+) = (-7.7 +/- 2.4 +/- 1.0 +/- 0.4) x 10(-2), x(-) = (2.5 +/- 2.5 +/- 1.0 +/- 0.5) x 10(-2), y(+) = (-2.2 +/- 2.5 +/- 0.4 +/- 1.0) x 10-2, and y(-) = (7.5 +/- 2.9 +/- 0.5 +/- 1.4) x 10(-2). The first, second, and third uncertainties are the statistical, the experimental systematic, and that associated with the precision of the strong-phase parameters. These are the most precise measurements of these observables and correspond to +/- = (62(-14)(+15))degrees, with a second solution at gamma -> gamma + 180 degrees, and r(B) = 0.080(-0.021)(+0.019), where r(B) is the ratio between the suppressed and favoured B decay amplitudes.
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