A search for the decay Bs0 → K̅∗0µ+µ− is presented using data sets corresponding to 1.0, 2.0 and 1.6 fb−1 of integrated luminosity collected during pp collisions with the LHCb experiment at centre-of-mass e...
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The decay of the narrow resonance B̅∗0s2 → B−K+ can be used to determine the B− momentum in partially reconstructed decays without any assumptions on the decay products of the B− meson. This technique is employed for...
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The Υ(1S)µ+µ− invariant-mass distribution is investigated for a possible exotic meson state composed of two b quarks and two b quarks, Xbbbb. The analysis is based on a data sample of pp collisions recorded...
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The decay Λ0b → Λ+c ppπ− is observed using pp collision data collected with the LHCb detector at centre-of-mass energies of √s = 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb−1. The ratio of bran...
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The B0s → χc2K+K− decay mode is observed and its branching fraction relative to the corresponding χc1 decay mode, in a ±15 MeV/c2 window around the φ mass, is found to be BB((BB0s0s→→χχcc21KK++KK−−)) = (1...
The Cabibbo-suppressed decay Λ0b → ψ(2S)pπ− is observed for the first time using a data sample collected by the LHCb experiment in proton-proton collisions corresponding to 1.0, 2.0 and 1.9 fb−1 of integrated lumi...
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The first observation of the Bs0→D¯0K+K− decay is reported, together with the most precise branching fraction measurement of the mode B0→D¯0K+K−. The results are obtained from an analysis of pp collision d...
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The first observation of the Bs0→D¯0K+K− decay is reported, together with the most precise branching fraction measurement of the mode B0→D¯0K+K−. The results are obtained from an analysis of pp collision data corresponding to an integrated luminosity of 3.0 fb−1. The data were collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. The branching fraction of the B0→D¯0K+K− decay is measured relative to that of the decay B0→D¯0π+π− to be B(B0→D¯0K+K−)B(B0→D¯0π+π−)=(6.9±0.4±0.3)%, where the first uncertainty is statistical and the second is systematic. The measured branching fraction of the Bs0→D¯0K+K− decay mode relative to that of the corresponding B0 decay is B(Bs0→D¯0K+K−)B(B0→D¯0K+K−)=(93.0±8.9±6.9)%. Using the known branching fraction of B0→D¯0π+π−, the values of B(B0→D¯0K+K−)=(6.1±0.4±0.3±0.3)×10−5 and B(Bs0→D¯0K+K−)=(5.7±0.5±0.4±0.5)×10−5 are obtained, where the third uncertainties arise from the branching fraction of the decay modes B0→D¯0π+π− and B0→D¯0K+K−, respectively.
The first observation of the Bs0→D¯*0ϕ decay is reported, with a significance of more than seven standard deviations, from an analysis of pp collision data corresponding to an integrated luminosity of 3 fb−1, c...
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The first observation of the Bs0→D¯*0ϕ decay is reported, with a significance of more than seven standard deviations, from an analysis of pp collision data corresponding to an integrated luminosity of 3 fb−1, collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. The branching fraction is measured relative to that of the topologically similar decay B0→D¯0π+π− and is found to be B(Bs0→D¯*0ϕ)=(3.7±0.5±0.3±0.2)×10−5, where the first uncertainty is statistical, the second systematic, and the third from the branching fraction of the B0→D¯0π+π− decay. The fraction of longitudinal polarization in this decay is measured to be fL=(73±15±4)%. The most precise determination of the branching fraction for the Bs0→D¯0ϕ decay is also obtained, B(Bs0→D¯0ϕ)=(3.0±0.3±0.2±0.2)×10−5. An upper limit, B(B0→D¯0ϕ)<2.0 (2.3)×10−6 at 90% (95%) confidence level is set. A constraint on the ω−ϕ mixing angle δ is set at |δ|<5.2° (5.5°) at 90% (95%) confidence level.
We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D0→K+π− to D0→K−π+ rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated lum...
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We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D0→K+π− to D0→K−π+ rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of 5.0 fb−1 recorded by the LHCb experiment from 2011 through 2016. Assuming charge-parity (CP) symmetry, the mixing parameters are determined to be x′2=(3.9±2.7)×10−5, y′=(5.28±0.52)×10−3, and RD=(3.454±0.031)×10−3. Without this assumption, the measurement is performed separately for D0 and D¯0 mesons, yielding a direct CP-violating asymmetry AD=(−0.1±9.1)×10−3, and magnitude of the ratio of mixing parameters 1.00<|q/p|<1.35 at the 68.3% confidence level. All results include statistical and systematic uncertainties and improve significantly upon previous single-measurement determinations. No evidence for CP violation in charm mixing is observed.
The production of Υ(nS) mesons (n = 1, 2, 3) in pPb and Pbp collisions at a centre-of-mass energy per nucleon pair √sNN = 8.16 TeV is measured by the LHCb experiment, using a data sample corresponding to an integrat...
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