LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2017). Measurement of CP observables in B-+/- -> DK*(+/-) decays using two- and four-body D final states. J. High Energy Phys., 11(11), 156–27pp.
Abstract: Measurements of CP observables in B-+/- -> DK*(+/-) decays are presented, where D denotes a superposition of D-0 and (D) over bar (0) meson states. Decays of the D meson to K-pi(+), K-K+, pi(-)pi(+), K-pi(+)pi(-)pi(+) and pi(-)pi(+)pi(-)pi(+) are used and the K*(+/-) meson is reconstructed in the K-S(0)pi(+/-) final state. This analysis uses a data sample of pp collisions collected with the LHCb experiment, corresponding to integrated luminosities of 1 fb(-1), 2 fb(-1) and 1.8 fb(-1) at centre-of-mass energies root s = 7TeV, 8TeV and 13TeV, respectively. The sensitivity of the results to the CKM angle gamma is discussed.
|
LHCb Collaboration(Aaij, R. et al), Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2021). Measurement of CP observables in B-+/- -> D-(*K-)(+/-) and B-+/- -> D-(*())pi(+/-) decays using two-body D final states. J. High Energy Phys., 04(4), 081–36pp.
Abstract: Measurements of CP observables in B-+/- -> D(*) K-+/- and B-+/- -> D(*) pi(+/-) decays are presented, where D(*) indicates a neutral D or D* meson that is an admixture of meson and anti-meson states. Decays of the D(*) meson to the D pi(0) and D gamma final states are partially reconstructed without inclusion of the neutral pion or photon. Decays of the D meson are reconstructed in the K-+/-pi(-/+), K+K-, and pi(+)pi(-) final states. The analysis uses a sample of charged B mesons produced in proton-proton collisions and collected with the LHCb experiment, corresponding to integrated luminosities of 2.0, 1.0, and 5.7 fb(-1) taken at centre-of-mass energies of 7, 8, and 13TeV, respectively. The measurements of partially reconstructed B-+/- -> D(*) K-+/- and B-+/- -> D(*)pi(+/-) with D -> K--/+pi(+/-) decays are the first of their kind, and a first observation of the B-+/- -> (D pi(0)) D*pi(+/-) decay is made with a significance of 6.1 standard deviations. All CP observables are measured with world-best precision, and in combination with other LHCb results will provide strong constraints on the CKM angle gamma.
|
LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., et al. (2020). Measurement of CP observables in B+/- -> DK+/- and B+/- -> D pi+/- with D -> KS0 K+/- pi-/+ decays. J. High Energy Phys., 06(6), 058–25pp.
Abstract: Measurements of CP observables in B-+/- -> DK +/- and B-+/- -> D pi (+/-) decays are presented, where D represents a superposition of D-0 and D<overbar>0 states. The D meson is reconstructed in the three-body final states KS0K +/- pi -/+ and KS0K -/+ pi +/-. The analysis uses samples of B mesons produced in proton-proton collisions, corresponding to an integrated luminosity of 1.0, 2.0, and 6.0 fb(-1) collected with the LHCb detector at centre-of-mass energies of <mml:msqrt>s</mml:msqrt> = 7, 8, and 13 TeV, respectively. These measurements are the most precise to date, and provide important input for the determination of the CKM angle gamma.
|
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.
|
LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2018). Measurement of CP asymmetry in B-s(0) -> (DsK +/-)-K-/+ decays. J. High Energy Phys., 03(3), 059–28pp.
Abstract: We report the measurements of the CP-violating parameters in B-s(0) -> (DsK +/-)-K--/+ decays observed in pp collisions, using a data set corresponding to an integrated luminosity of 3.0 fb(-1) recorded with the LHCb detector. We measure C-f = 0.73 +/- 0.14 +/- 0.05, A(f)(Delta Gamma) = 0.39 +/- 0.28 +/- 0.15, A(<(f)over) (Delta Gamma)(bar>) = 0.31 +/- 0.28 +/- 0.15, S-f = -0.52 +/- 0.20 +/- 0.07, S-(f) over bar = -0.49 +/- 0.20 +/- 0.07, where the uncertainties are statistical and systematic, respectively. These parameters are used together with the world-average value of the B-s(0) mixing phase, -2 beta(s), to obtain a measurement of the CKM angle gamma from B-s(0) -> (DsK +/-)-K--/+ decays, yielding gamma – (128 (+17)(-22))degrees modulo 180 degrees, where the uncertainty contains both statistical and systematic contributions. This corresponds to 3.8 sigma evidence for CP violation in the interference between decay and decay after mixing.
|