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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2015). Measurement of CP violation parameters and polarisation fractions in B-s(0) -> J/psi(K)over-bar*(0) decays. J. High Energy Phys., 11(11), 082–38pp.
Abstract: The first measurement of CP asymmetries in the decay B-s(0) -> J/psi(K) over bar*(892)(0) and an updated measurement of its branching fraction and polarisation fractions are presented. The results are obtained using data corresponding to an integrated luminosity of 3.0 fb (-1) of proton-proton collisions recorded with the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Together with constraints from B-0 -> J/psi rho(0), the results are used to constrain additional contributions due to penguin diagrams in the CP-violating phase phi(s), measured through B-s(0) decays to charmonium.
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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. (2015). Measurement of the time-dependent CP asymmetries in B-s(0) -> J/psi K-S(0). J. High Energy Phys., 06(6), 131–22pp.
Abstract: The first measurement of decay-time-dependent CP asymmetries in the decay B-S(0) -> J/psi K-S(0) and an updated measurement of the ratio of branching fractions B(B-S(0) -> J/psi K-S(0))/B(B-0 -> J/psi K-S(0)) are presented. The results are obtained using data corresponding to an integrated luminosity of 3.0 fb(-1) of proton-proton collisions recorded with the LHCb detector at centre-of-mass energies of 7 and 8 TeV. The results on the CP asymmetries are A(Delta Gamma)(B-S(0) -> J/psi K-S(0)) = 0.49 +/- (0.77)(0.65)(stat) +/- 0.06(syst), C-dir(B-S(0) -> J/psi K-S(0)) = -0.28 +/- 0.41(stat) +/- 0.08(syst), S-mix(B-S(0) -> J/psi K-S(0)) = -0.08 +/- 0.40(stat) +/- 0.08(syst). The ratio B(B-S(0) -> J/psi K-S(0))/B(B-0 -> J/psi K-S(0)) is measured to be 0.0431 +/- 0.0017(stat) +/- 0.0012(syst) +/- 0.0025(f(s)/f(d)), where the last uncertainty is due to the knowledge of the B-S(0) and B-0 production fractions.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2015). Measurement of the time-integrated CP asymmetry in D-0 -> (KSKS0)-K-0 decays. J. High Energy Phys., 10(10), 055–15pp.
Abstract: The time-integrated CP asymmetry in the decay D-0 -> (KSKS0)-K-0 is measured using 3 fb(-1) of proton-proton collision data collected by the LHCb experiment at centreof- mass energies of 7 and 8TeV. The flavour of the D-0 meson is determined by use of the decay D*(+) -> D-0 pi(+) and its charge conjugate mode. The result is A(CP) = -0.029 +/- 0.052 +/- 0.022, where the first uncertainty is statistical and the second systematic. The result is consistent with Standard Model expectations and improves the uncertainty with respect to the only previous measurement of this quantity by more than a factor of three.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2016). Measurement of the CKM angle gamma using B (0) -> DK (*0) with D -> K-S(0) pi (+) pi (-) decays. J. High Energy Phys., 08(8), 137–30pp.
Abstract: A model-dependent amplitude analysis of the decay B (0) -> D(K (S) (0) pi (+) pi (-))K (au 0) is performed using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb(-1), recorded at and 8 TeV by the LHCb experiment. The CP violation observables x (+/-) and y (+/-), sensitive to the CKM angle gamma, are measured to be x- = 0.15 +/- 0.14 +/- 0.03 +/- 0.01; y- = 0.25 +/- 0.15 +/- 0.06 +/- 0.01; x+ = 0.05 +/- 0.24 +/- 0.04 +/- 0.01; y+ = 0.65(-0.23)(+0.24) +/- 0.08 +/- 0.01; where the first uncertainties are statistical, the second systematic and the third arise from the uncertainty on the D -> K (S) (0) pi (+) pi (-) amplitude model. These are the most precise measurements of these observables. They correspond to gamma = (80 (- 22) (+ 21) )A degrees and , where is the magnitude of the ratio of the suppressed and favoured B (0) -> DK (+) pi (-) decay amplitudes, in a K pi mass region of +/- 50 MeV around the K (*)(892)(0) mass and for an absolute value of the cosine of the K (*0) decay angle larger than 0.4.
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