The oscillation frequency, Formula: see text, of Formula: see text mesons is measured using semileptonic decays with a Formula: see text or Formula: see text meson in the final state. The data sample ...corresponds to 3.0Formula: see text of
collisions, collected by the LHCb experiment at centre-of-mass energies Formula: see text = 7 and 8Formula: see text. A combination of the two decay modes gives Formula: see text, where the first uncertainty is statistical and the second is systematic. This is the most precise single measurement of this parameter. It is consistent with the current world average and has similar precision.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Abstract A measurement of the differential branching fraction of the decay B 0 arrow right K (892)0 mu + mu - is presented ...together with a determination of the S-wave fraction of the K + pi - system in the decay B 0 arrow right K +pi- mu + mu -. The analysis is based on pp-collision data corresponding to an integrated luminosity of 3 fb-1 collected with the LHCb experiment. The measurements are made in bins of the invariant mass squared of the dimuon system, q 2. Precise theoretical predictions for the differential branching fraction of B 0 arrow right K (892)0 mu + mu - decays are available for the q 2 region 1.1 < q 2 < 6.0 GeV2 /c 4. In this q 2 region, for the K +pi- invariant mass range 796 < m Kpi < 996 MeV/c 2, the S-wave fraction of the K +pi- system in B 0 arrow right K +pi- mu + mu - decays is found to be ... and the differential branching fraction of B 0 arrow right K (892)0 mu + mu - decays is determined to be ... The differential branching fraction measurements presented are the most precise to date and are found to be in agreement with Standard Model predictions. Figure not available: see fulltext.
The CP asymmetry in the mixing of B_{s}^{0} and Bover ¯_{s}^{0} mesons is measured in proton-proton collision data corresponding to an integrated luminosity of 3.0 fb^{-1}, recorded by the LHCb ...experiment at center-of-mass energies of 7 and 8 TeV. Semileptonic B_{s}^{0} and Bover ¯_{s}^{0} decays are studied in the inclusive mode D_{s}^{∓}μ^{±}νover (-)_{μ}X with the D_{s}^{∓} mesons reconstructed in the K^{+}K^{-}π^{∓} final state. Correcting the observed charge asymmetry for detection and background effects, the CP asymmetry is found to be a_{sl}^{s}=(0.39±0.26±0.20)%, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of a_{sl}^{s} to date. It is consistent with the prediction from the standard model and will constrain new models of particle physics.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Abstract A model-dependent amplitude analysis of the decay B 0arrow rightD(K S 0 pi + pi -)K 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 γ, are measured to be ... where the first uncertainties are statistical, the second systematic and the third arise from the uncertainty on the Darrow rightK S 0 pi + pi - amplitude model. These are the most precise measurements of these observables. They correspond to γ=(80 -22 +21 )° and ..., where ... is the magnitude of the ratio of the suppressed and favoured B 0 arrow right DK + pi - decay amplitudes, in a Kpi 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. Figure not available: see fulltext.
Charm meson oscillations are observed in a time-dependent analysis of the ratio of D^{0}→K^{+}π^{-}π^{+}π^{-} to D^{0}→K^{-}π^{+}π^{-}π^{+} 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}^{K3π} and the product of the coherence factor R_{D}^{K3π} and a charm mixing parameter y_{K3π}^{'}. The constraints measured are r_{D}^{K3π}=(5.67±0.12)×10^{-2}, which is the most precise determination to date, and R_{D}^{K3π}y_{K3π}^{'}=(0.3±1.8)×10^{-3}, which provides useful input for determinations of the CP-violating phase γ in B^{±}→DK^{±}, D→K^{∓}π^{±}π^{∓}π^{±} decays. The analysis also gives the most precise measurement of the D^{0}→K^{+}π^{-}π^{+}π^{-} branching fraction, and the first observation of D^{0}-Dover ¯^{0} oscillations in this decay mode, with a significance of 8.2 standard deviations.
A search for CP violation in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is performed using pp collision data, corresponding to an integrated luminosity of 3 fb^{-1}, collected using the LHCb ...detector at center-of-mass energies of 7 and 8 TeV. The flavor of the charm meson is inferred from the charge of the pion in D^{*+}→D^{0}π^{+} and D^{*-}→Dover ¯^{0}π^{-} decays. The difference between the CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, ΔA_{CP}≡A_{CP}(K^{-}K^{+})-A_{CP}(π^{-}π^{+}), is measured to be -0.10±0.08(stat)±0.03(syst)%. This is the most precise measurement of a time-integrated CP asymmetry in the charm sector from a single experiment.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Abstract A binned Dalitz plot analysis of the decays B 0 arrow right DK 0, with Darrow rightK S 0 pi + pi - and Darrow ...rightK S 0 K + K -, is performed to measure the observables x ± and y ±, which are related to the CKM angle γ and the hadronic parameters of the decays. The D decay strong phase variation over the Dalitz plot is taken from measurements performed at the CLEO-c experiment, making the analysis independent of the D decay model. With a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb -1, collected by the LHCb experiment, the values of the CP violation parameters are found to be x + = 0.05 ± 0.35 ± 0.02, x - = -0.31 ± 0.20 ± 0.04, y + = -0.81 ± 0.28 ± 0.06 and y - = 0.31 ± 0.21 ± 0.05, where the first uncertainties are statistical and the second systematic. These observables correspond to values γ = (71 ± 20)°, ... and ... The parameters ... and ... are the magnitude ratio and strong phase difference between the suppressed and favoured B 0 decay amplitudes, and have been measured in a region of ±50 MeV/c 2 around the K (892)0 mass and with the magnitude of the cosine of the K (892)0 helicity angle larger than 0.4. Figure not available: see fulltext.
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Abstract We perform a search for near-threshold Xi b 0 resonances decaying to Xi b - pi + in a sample of proton-proton ...collision data corresponding to an integrated luminosity of 3 fb-1 collected by the LHCb experiment. We observe one resonant state, with the following properties: ... This confirms the previous observation by the CMS collaboration. The state is consistent with the J P=3/2+ Xi b 0 resonance expected in the quark model. This is the most precise determination of the mass and the first measurement of the natural width of this state. We have also measured the ratio ...Figure not available: see fulltext.
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