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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2016). Observation of the Lambda(0)(b) -> Lambda phi decay. Phys. Lett. B, 759, 282–292.
Abstract: The Lambda(0)(b) -> Lambda phi decay is observed using data corresponding to an integrated luminosity of 3.0 fb(-1) recorded by the LHCb experiment. The decay proceeds at leading order via a b -> s<(s)double over bar>s loop transition and is therefore sensitive to the possible presence of particles beyond the Standard Model. A first observation is reported with a significance of 5.9 standard deviations. The value of the branching fraction is measured to be (5.18 +/- 1.04 +/- 0.35(-0.62)(+0.67)) x 10(-6), where the first uncertainty is statistical, the second is systematic, and the third is related to external inputs. Triple-product asymmetries are measured to be consistent with zero.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2016). First Observation of D-0 – (D)over-bar(0) Oscillations in D-0 -> K+pi(-)pi(+)pi(-) Decays and Measurement of the Associated Coherence Parameters. Phys. Rev. Lett., 116(24), 241801–10pp.
Abstract: Charm meson oscillations are observed in a time-dependent analysis of the ratio of D-0 -> K+pi(-)pi(+)pi(-) to D-0 -> K-pi(+)pi(-)pi(+) decay rates, using data corresponding to an integrated luminosity of 3.0 fb(-1) recorded by the LHCb experiment. The measurements presented are sensitive to the phase-space averaged ratio of doubly Cabibbo-suppressed to Cabibbo-favored amplitudes r(D)(K3 pi) and the product of the coherence factor R-D(K3 pi) and a charm mixing parameter y'(K3 pi). The constraints measured are r(D)(K3 pi) = (5.67 +/- 0.12) x 10(-2), which is the most precise determination to date, and R-D(K3 pi) y'(K3 pi) = (0.3 +/- 1.8) x 10(-3), which provides useful input for determinations of the CP-violating phase gamma in B-+/- -> DK +/-, D -> K--/+pi(+/-)pi(-/+)pi(+/-) decays. The analysis also gives the most precise measurement of the D-0 -> K+pi(-)pi(+)pi(-) branching fraction, and the first observation of D-0-(D) over bar (0) oscillations in this decay mode, with a significance of 8.2 standard deviations.
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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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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2016). First observation of the decay B-s(0) -> (KSK)-K-0*(892)(0) at LHCb. J. High Energy Phys., 01(1), 012–17pp.
Abstract: A search for B-(s)(0) -> K-S (0) K*(892)(0) decays is performed using pp collision data, corresponding to an integrated luminosity of 1.0 fb(-1), collected with the LHCb detector at a centre-of-mass energy of 7 TeV. The B-s (0) -> (KSK)-K-0*(892)(0) decay is observed for the first time, with a significance of 7.1 standard deviations. The branching fraction is measured to be B(B-s(0) -> (K) over bar K-0*(892)(0)) + B(B-s(0) -> K-0(K) over bar*(892)(0)) = (16.4 +/- 3.4 +/- 2.3) x10(-6), where the first uncertainty is statistical and the second is systematic. No evidence is found for the decay B-0 ->(KSK)-K-0*(892)(0) and an upper limit is set on the branching fraction, B(B-0 -> (K) over bar K-0*(892)(0)) + B(B-0 -> K-0(K) over bar*(892)(0)) < 0.96 x 10(-6) , at 90 % confidence level. All results are consistent with Standard Model predictions.
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LHCb Collaboration(Aaij, R. et al), Martinez-Vidal, F., Oyanguren, A., Ruiz Valls, P., & Sanchez Mayordomo, C. (2016). Study of D-(*())(+)(sJ) mesons decaying to D*K-+(S)0 and D*K-0(+) final states. J. High Energy Phys., 02(2), 133–26pp.
Abstract: A search is performed for D-sJ(()*()+) mesons in the reactions pp -> D*(+KSX)-X-0 and pp -> D*(K+X)-K-0 using data collected at centre-of-mass energies of 7 and 8 TeV with the LHCb detector. For the D*K-+(S)0 final state, the decays D*(+) -> D-0 pi(+) with D-0 -> K-pi(+) and D-0 -> K-pi(+)pi(+)pi(-) are used. For D*K-0(+), the decay D*(0) -> D-0 pi(0) with D-0 -> K-pi(+) is used. A prominent D-s1(2536)(+) signal is observed in both D*K-+(S)0 and D*K-0(+) final states. The resonances D*(s1)(2700)(+) and D*(s3)(2860)(+) are also observed, yielding information on their properties, including spin-parity assignments. The decay D*(s2)(2573)(+) -> D*(+) K-S(0) is observed for the first time, at a significance of 6.9 sigma, and its branching fraction relative to the D*(s2)(2573)(+) -> (D+KS0) decay mode is measured.
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