Search

The first full angular analysis of the B0→D∗−D∗+s decay is performed using 6 fb−1 of pp collision data collected with the LHCb experiment at a centre-of-mass energy of 13 TeV. The D∗+s→D+sγ and D*− → D¯¯¯¯0π− vector meson decays are used with the subsequent D+s → K+K−π+ and D¯¯¯¯0 → K+π− decays. All helicity amplitudes and phases are measured, and the longitudinal polarisation fraction is determined to be fL = 0.578 ± 0.010 ± 0.011 with world-best precision, where the first uncertainty is statistical and the second is systematic. The pattern of helicity amplitude magnitudes is found to align with expectations from quark-helicity conservation in B decays. The ratio of branching fractions [ℬ(B0→D∗−D∗+s) × ℬ(D∗+s→D+sγ)]/ℬ(B0 → D*−D+s) is measured to be 2.045 ± 0.022 ± 0.071 with world-best precision. In addition, the first observation of the Cabibbo-suppressed Bs → D*−D+s decay is made with a significance of seven standard deviations. The branching fraction ratio ℬ(Bs → D*−D+s)/ℬ(B0 → D*−D+s) is measured to be 0.049 ± 0.006 ± 0.003 ± 0.002, where the third uncertainty is due to limited knowledge of the ratio of fragmentation fractions SI

A search for the decay B0S→K¯∗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 energies of 7, 8 and 13 TeV, respectively. An excess is found over the background-only hypothesis with a significance of 3.4 standard deviations. The branching fraction of the B0S→K¯∗0μ+μ− decay is determined to be B(B0s→K¯∗0μ+μ−)=[2.9±1.0(stat)±0.2(syst)±0.3(norm)]×10−8, where the first and second uncertainties are statistical and systematic, respectively. The third uncertainty is due to limited knowledge of external parameters used to normalise the branching fraction measurement. SI

Amplitude models are constructed to describe the resonance structure of D0 → K− π + π + π − and D0 → K+ π − π − π + decays using pp collision data collected at centre-of-mass energies of 7 and 8 TeV with the LHCb experiment, corresponding to an integrated luminosity of 3.0 f b−1. The largest contributions to both decay amplitudes are found to come from axial resonances, with decay modes D0 → a1(1260) +K− and D0 → K1(1270/1400) + π − being prominent in D0 → K− π + π + π − and D0 → K+ π − π − π +, respectively. Precise measurements of the lineshape parameters and couplings of the a1(1260) +, K1(1270) − and K(1460) − resonances are made, and a quasi model-independent study of the K(1460) − resonance is performed. The coherence factor of the decays is calculated from the amplitude models to be RK3π = 0.459 ± 0.010 (stat) ± 0.012 (syst)±0.020 (model), which is consistent with direct measurements. These models will be useful in future measurements of the unitary-triangle angle γ and studies of charm mixing and CP violation SI

A Dalitz plot analysis of B0 → ηc(1S)K +π− decays is performed using data samples of pp collisions collected with the LHCb detector at centre-of-mass energies of √s = 7, 8 and 13 TeV, corresponding to a total integrated luminosity of 4.7 fb−1. A satisfactory description of the data is obtained when including a contribution representing an exotic ηc(1S)π− resonant state. The significance of this exotic resonance is more than three standard deviations, while its mass and width are 4096 ± 20 +18 −22 MeV and 152±58 +60 −35 MeV, respectively. The spin-parity assignments J P = 0+ and J P = 1− are both consistent with the data. In addition, the first measurement of the B0 → ηc(1S)K +π− branching fraction is performed and gives B(B0→ ηc(1S)K +π−) = (5.73 ± 0.24 ± 0.13 ± 0.66) × 10−4, where the first uncertainty is statistical, the second systematic, and the third is due to limited knowledge of external branching fractions SI

The decay Λ0b→Λ+cppπ−is observed using ppcollision data collected with the LHCb detector at centre-of-mass energies of √s=7and 8Tev, corresponding to an integrated luminosity of 3fb−1. The ratio of branching fractions between Λ0b→Λ+cppπ−and Λ0b→Λ+cπ−decays is measured to be B(Λ0 b →Λ + c ppπ− ) B(Λ0 b →Λ + c π−) = 0.0540±0.0023±0.0032. Two resonant structures are observed in the Λ+cπ−mass spectrum of the Λ0b→Λ+cppπ−decays, corresponding to the Σc(2455)0and Σ∗c(2520)0states. The ratios of branching fractions with respect to the decay Λ0b→Λ+cppπ−are B(Λ0 b →Σ0 c pp)×B(Σ0 c →Λ + c π− ) B(Λ0 b →Λ + c ppπ−) = 0.089±0.015±0.006, B(Λ0 b →Σ ∗0 c pp)×B(Σ ∗0 c →Λ + c π− ) B(Λ0 b →Λ + c ppπ−) = 0.119±0.020±0.014. In all of the above results, the first uncertainty is statistical and the second is systematic. The phase space is also examined for the presence of dibaryon resonances. No evidence for such resonances is found. SI

A search for CPviolation in Λ0b→pK−and Λ0b→pπ−decays is presented using a sample of ppcollisions collected with the LHCb detector and corresponding to an integrated luminosity of 3.0fb−1. The CP-violating asymmetries are measured to be ApK−CP=−0.020 ±0.013 ±0.019and Apπ−CP=−0.035 ±0.017 ±0.020, and their difference ApK−CP−Apπ−CP=0.014 ±0.022 ±0.010, where the first uncertainties are statistical and the second systematic. These are the most precise measurements of such asymmetries to date. SI

The production of ϒ(nS) mesons (n = 1, 2, 3) in pPb and Pbp collisions at a centre-of-mass energy per nucleon pair \( \sqrt{s_{\mathrm{NN}}}=8.16 \) TeV is measured by the LHCb experiment, using a data sample corresponding to an integrated luminosity of 31.8 nb−1. The ϒ(nS) mesons are reconstructed through their decays into two opposite-sign muons. The measurements comprise the differential production cross-sections of the ϒ(1S) and ϒ(2S) states, their forward-to-backward ratios and nuclear modification factors. The measurements are performed as a function of the transverse momentum pT and rapidity in the nucleon-nucleon centre-of-mass frame y* of the ϒ(nS) states, in the kinematic range pT < 25 GeV/c and 1.5 < y* < 4.0 (−5.0 < y* < −2.5) for pPb (Pbp) collisions. In addition, production cross-sections for ϒ(3S) are measured integrated over phase space and the production ratios between all three ϒ(nS) states are determined. Suppression for bottomonium in proton-lead collisions is observed, which is particularly visible in the ratios. The results are compared to theoretical models. SI

Measurements of CPobservables in B±→D(∗)K±and B±→D(∗)π±decays are presented, where D(∗)indicates a neutral Dor D∗meson that is an admixture of D(∗)0and ¯ D(∗)0states. Decays of the D∗meson to the Dπ0and Dγfinal states are partially reconstructed without inclusion of the neutral pion or photon, resulting in distinctive shapes in the Bcandidate invariant mass distribution. Decays of the Dmeson are fully reconstructed in the K±π∓, K+K−and π+π−final states. The analysis uses a sample of charged Bmesons produced in ppcollisions collected by the LHCb experiment, corresponding to an integrated luminosity of 2.0, 1.0 and 2.0fb−1taken at centre-of-mass energies of √s=7, 8 and 13TeV, respectively. The study of B±→D∗K±and B±→D∗π±decays using a partial reconstruction method is the first of its kind, while the measurement of B±→DK±and B±→Dπ±decays is an update of previous LHCb measurements. The B±→DK±results are the most precise to date. SI

The B¯0s→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 B(B¯0s→χc2K+K−)B(B¯0s→χc1K+K−)=(17.1±3.1±0.4±0.9)%, where the first uncertainty is statistical, the second systematic and the third due to the knowledge of the branching fractions of radiative χc decays. The decay mode B¯0s→χc1K+K− allows the B0s mass to be measured as m(B0s)=5366.83±0.25±0.27 MeV/c2, where the first uncertainty is statistical and the second systematic. A combination of this result with other LHCb determinations of the B 0s mass is made. SI

A measurement of Z → τ +τ − production cross-section is presented using data, corresponding to an integrated luminosity of 2 fb−1, from pp collisions at √s=8 TeV collected by the LHCb experiment. The τ +τ − candidates are reconstructed in final states with the first tau lepton decaying leptonically, and the second decaying either leptonically or to one or three charged hadrons. The production cross-section is measured for Z bosons with invariant mass between 60 and 120 GeV/c2, which decay to tau leptons with transverse momenta greater than 20 GeV/c and pseudorapidities between 2.0 and 4.5. The cross-section is determined to be σpp→Z→τ+τ−=95.8±2.1±4.6±0.2±1.1 pb, where the first uncertainty is statistical, the second is systematic, the third is due to the LHC beam energy uncertainty, and the fourth to the integrated luminosity uncertainty. This result is compatible with NNLO Standard model predictions. The ratio of the cross-sections for Z → τ+τ− to Z → μ+μ− (Z → e+e−), determined to be 1.01 ± 0.05 (1.02 ± 0.06), is consistent with the lepton-universality hypothesis in Z decays. SI

A search for CP violation in the decay Λ0b → pK − μ + μ − is presented. This decay is mediated by flavour-changing neutral-current transitions in the Standard Model and is potentially sensitive to new sources of CP violation. The study is based on a data sample of proton-proton collisions recorded with the LHCb experiment, corresponding to an integrated luminosity of 3 fb−1. The Λ0b → pK − μ + μ − decay is observed for the first time, and two observables that are sensitive to different manifestations of CP violation are measured, ΔACP≡ACP(Λ0b→pK−μ+μ−)−ACP(Λ0b→pK−J/ψ) and a aTˆ-oddCP, where the latter is based on asymmetries in the angle between the μ + μ − and pK − decay planes. SI

Measurements of CP observables in B± → DK*± decays are presented, where D denotes a superposition of D0 and D¯0 meson states. Decays of the D meson to K−π+, K−K+, π−π+, K−π+π−π+ and π−π+π−π+ are used and the K*± meson is reconstructed in the K 0Sπ± 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 √s=7 TeV, 8 TeV and 13 TeV, respectively. The sensitivity of the results to the CKM angle γ is discussed. SI

The production cross-section of J/ψ pairs is measured using a data sample of pp collisions collected by the LHCb experiment at a centre-of-mass energy of √s=13 TeV, corresponding to an integrated luminosity of 279 ±11 pb−1. The measurement is performed for J/ψ mesons with a transverse momentum of less than 10 GeV/c in the rapidity range 2.0 < y < 4.5. The production cross-section is measured to be 15.2 ± 1.0 ± 0.9 nb. The first uncertainty is statistical, and the second is systematic. The differential cross-sections as functions of several kinematic variables of the J/ψ pair are measured and compared to theoretical predictions. SI

Kinematic correlations for pairs of beauty hadrons, produced in high energy proton-proton collisions, are studied. The data sample used was collected with the LHCb experiment at centre-of-mass energies of 7 and 8 TeV and corresponds to an integrated luminosity of 3 fb−1. The measurement is performed using inclusive b → J/ψX decays in the rapidity range 2 < yJ/ψ < 4.5. The observed correlations are in good agreement with theoretical predictions. SI

Production cross-sections of prompt charm mesons are measured using data from pp collisions at the LHC at a centre-of-mass energy of 5 TeV. The data sample corresponds to an integrated luminosity of 8.60 ± 0.33 pb−1 collected by the LHCb experiment. The production cross-sections of D 0, D +, D +s, and D ∗+ mesons are measured in bins of charm meson transverse momentum, p T, and rapidity, y. They cover the rapidity range 2.0 < y < 4.5 and transverse momentum ranges 0 < p T < 10 GeV/c for D 0 and D + and 1 < p T < 10 GeV/c for D +s and D ∗+ mesons. The inclusive cross-sections for the four mesons, including charge-conjugate states, within the range of 1 < p T < 8 GeV/c are determined to be σ(pp→D0X)=1004±3±54μb,σ(pp→D+X)=402±2±30μb,σ(pp→D+sX)=170±4±16μb,σ(pp→D∗+X)=421±5±36μb, where the uncertainties are statistical and systematic, respectively. SI

The observation of the decay Ξ−b→J/ψΛK−is reported, using a data sample corresponding to an integrated luminosity of 3 fb−1, collected by the LHCb detector in ppcollisions at centre-of-mass energies of 7and 8 TeV. The production rate of Ξ−bbaryons detected in the decay Ξ−b→J/ψΛK−is measured relative to that of Λ0bbaryons using the decay Λ0b→J/ψΛ. Integrated over the b-baryon transverse momentum pT

The production of J/ψ mesons is studied in proton-lead collisions at the centre-of-mass energy per nucleon pair √ sNN = 8.16 TeVwith the LHCb detector at the LHC. The double differential cross-sections of prompt and nonprompt J/ψ production are measured as a function of the J/ψ transverse momentum and rapidity in the nucleon–nucleon centre-of-mass frame. Forward-to-backward ratios and nuclear modification factors are determined. The results are compared with theoretical calculations based on collinear factorisation using nuclear parton distribution functions, on the colour glass condensate or on coherent energy loss models. SI

A search for the non-resonant decays B 0s → μ + μ − μ + μ − and B 0 → μ + μ − μ + μ − is presented. The measurement is performed using the full Run 1 data set collected in proton-proton collisions by the LHCb experiment at the LHC. The data correspond to integrated luminosities of 1 and 2 fb−1 collected at centre-of-mass energies of 7 and 8 TeV, respectively. No signal is observed and upper limits on the branching fractions of the non-resonant decays at 95% confidence level are determined to be B(B0s→μ+μ−μ+μ−)

Production of prompt D0 mesons is studied in proton-lead and lead-proton collisions recorded at the LHCb detector at the LHC. The data sample corresponds to an integrated luminosity of 1.58±0.02 nb−1 recorded at a nucleon-nucleon centre-of-mass energy of √sNN=5 TeV. Measurements of the differential cross-section, the forward-backward production ratio and the nuclear modification factor are reported using D 0 candidates with transverse momenta less than 10 GeV/c and rapidities in the ranges 1.5 < y ∗ < 4.0 and −5.0 < y ∗ < −2.5 in the nucleon-nucleon centre-of-mass system. SI

The charmless three-body decays B 0( s) → K0Sh+h′ − (where h(′) = π, K) are analysed using a sample of pp collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 3 fb−1. The branching fractions are measured relative to that of the B0 → K0Sπ+π− decay, and are determined to be: B(B0→K0SK±π∓)B(B0→K0SK+π−)=0.123±0.009(stat)±0.015(syst),B(B0→K0SK+K−)B(B0→K0Sπ+π−)=0.549±0.018(stat)±0.033(syst),B(B0s→K0Sπ+π−)B(B0→K0Sπ+π−)=0.191±0.027(stat)±0.031(syst)±0.011(fs/fd),B(B0s→K0SK±π∓)B(B0→K0Sπ+π−)=1.70±0.07(stat)±0.11(syst)±0.10(fs/fd),B(B0s→K0SK+K−)B(B0→K0Sπ+π−)∈[0.008−0.051]at 90% confidencelevel, where fs/fd represents the ratio of hadronisation fractions of the B0s and B0 mesons. SI

A test of lepton universality, performed by measuring the ratio of the branching fractions of the B 0 → K *0 μ + μ − and B 0 → K *0 e + e − decays, RK∗0, is presented. The K *0 meson is reconstructed in the final state K + π −, which is required to have an invariant mass within 100 MeV/c 2 of the known K *(892)0 mass. The analysis is performed using proton-proton collision data, corresponding to an integrated luminosity of about 3 fb−1, collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The ratio is measured in two regions of the dilepton invariant mass squared, q 2, to be RK∗0={0.66+−0.110.07(stat)±0.03(syst)for0.045

A search for the decay K0S→μ+μ− is performed, based on a data sample of proton-proton collisions corresponding to an integrated luminosity of 3 fb −1 , collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV . The observed yield is consistent with the background-only hypothesis, yielding a limit on the branching fraction of BF(K0S→μ+μ−)

Bose-Einstein correlations of same-sign charged pions, produced in proton-proton collisions at a 7 TeV centre-of-mass energy, are studied using a data sample collected by the LHCb experiment. The signature for Bose-Einstein correlations is observed in the form of an enhancement of pairs of like-sign charged pions with small four-momentum difference squared. The charged-particle multiplicity dependence of the Bose-Einstein correlation parameters describing the correlation strength and the size of the emitting source is investigated, determining both the correlation radius and the chaoticity parameter. The measured correlation radius is found to increase as a function of increasing charged-particle multiplicity, while the chaoticity parameter is seen to decrease. SI

The decays of B 0s and B¯0s mesons into the J/ψK + K − final state are studied in the K + K − mass region above the ϕ(1020) meson in order to determine the resonant substructure and measure the CP-violating phase, ϕ s , the decay width, Γ s , and the width difference between light and heavy mass eigenstates, ΔΓ s . A decay-time dependent amplitude analysis is employed. The data sample corresponds to an integrated luminosity of 3 fb−1 produced in 7 and 8 TeV pp collisions at the LHC, collected by the LHCb experiment. The measurement determines ϕ s = 119 ± 107 ± 34 mrad. A combination with previous LHCb measurements using similar decays into the J/ψπ + π − and J/ψϕ(1020) final states gives ϕ s = 1 ± 37 mrad, consistent with the Standard Model prediction. SI

The production of B± mesons is studied in pp collisions at centre-of-mass energies of 7 and 13 TeV, using B± → J/ψ K± decays and data samples corresponding to 1.0 fb−1 and 0.3 fb−1, respectively. The production cross-sections summed over both charges and integrated over the transverse momentum range 0 < pT < 40 GeV/c and the rapidity range 2.0 < y < 4.5 are measured to be σ(pp→B±X,s√=7TeV)=43.0±0.2±2.5±1.7μb,σ(pp→B±X,s√=13TeV)=86.6±0.5±5.4±3.4μb, where the first uncertainties are statistical, the second are systematic, and the third are due to the limited knowledge of the B± → J/ψ K± branching fraction. The ratio of the cross-section at 13 TeV to that at 7 TeV is determined to be 2.02 ± 0.02 (stat) ± 0.12 (syst). Differential cross-sections are also reported as functions of pT and y. All results are in agreement with theoretical calculations based on the state-of-art fixed next-to-leading order quantum chromodynamics. SI

The first observation of the decay ηc(2S) →pp¯ pis reported using proton–proton collision data corre-sponding to an integrated luminosity of 3.0fb−1recorded by the LHCb experiment at centre-of-mass energies of7 and 8TeV. The ηc(2S)resonance is produced in the decay B+→[c¯ c]K+. The product of branching fractions normalised to that for the J/ψintermediate state, Rηc(2S), is measured to be Rηc (2S) ≡ B(B+→ηc(2S)K+ )×B(ηc(2S)→ p¯p ) B(B+→ J/ψ K+)×B( J/ψ → p¯p ) = (1.58±0.33±0.09)×10−2, where the first uncertainty is statistical and the second systematic. No signals for the decays B+→X(3872)(→p¯ p)K+and B+→ψ(3770)(→p¯ p)K+are seen, and the 95% confidence level upper limits on their relative branching ratios are found to be RX(3872)

A search is presented for long-lived particles with a mass between 25 and 50GeV/c2 and a lifetime between 2 and 500 ps, using proton–proton collision data corresponding to an integrated luminosity of 2.0fb−1, collected by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. The particles are assumed to be pair-produced in the decay of a 125GeV/c2 Standard-Model-like Higgs boson. The experimental signature is a single long-lived particle, identified by a displaced vertex with two associated jets. No excess above background is observed and limits are set on the production cross-section as a function of the mass and lifetime of the long-lived particle. SI

An amplitude analysis of the decay Λ0b → D0 pπ − is performed in the part of the phase space containing resonances in the D0 p channel. The study is based on a data sample corresponding to an integrated luminosity of 3.0 fb−1 of pp collisions recorded by the LHCb experiment. The spectrum of excited Λ +c states that decay into D0 p is studied. The masses, widths and quantum numbers of the Λc(2880)+ and Λc(2940)+ resonances are measured. The constraints on the spin and parity for the Λc(2940)+ state are obtained for the first time. A near-threshold enhancement in the D0 p amplitude is investigated and found to be consistent with a new resonance, denoted the Λc(2860)+, of spin 3/2 and positive parity. SI

Using decays to φ-meson pairs, the inclusive production of charmonium states in b-hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0 fb−1, collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. Denoting by BC ≡ B(b → CX) × B(C → φφ) the inclusive branching fraction of a b hadron to a charmonium state C that decays into a pair of φ mesons, ratios RC1 C2 ≡ BC1/BC2 are determined as Rχc0 ηc(1S) = 0.147 ± 0.023 ± 0.011, Rχc1 ηc(1S) = 0.073 ± 0.016 ± 0.006, Rχc2 ηc(1S) = 0.081 ± 0.013 ± 0.005, Rχc1 χc0 = 0.50 ± 0.11 ± 0.01, Rχc2 χc0 = 0.56 ± 0.10 ± 0.01 and Rηc(2S) ηc(1S) = 0.040 ± 0.011 ± 0.004. Here and below the first uncertainties are statistical and the second systematic. Upper limits at 90% confidence level for the inclusive production of X(3872), X(3915) and χc2(2P) states are obtained as RX(3872) χc1 < 0.34, RX(3915) χc0 < 0.12 and Rχc2(2P) χc2 < 0.16. Differential cross-sections as a function of transverse momentum are measured for the ηc(1S) and χc states. The branching fraction of the decay B0 s → φφφ is measured for the first time, B(B0 s → φφφ) = (2.15±0.54± 0.28±0.21B)×10−6. Here the third uncertainty is due to the branching fraction of the decay B0 s → φφ, which is used for normalization. No evidence for intermediate resonances is seen. A preferentially transverse φ polarization is observed. Themeasurements allow the determination of the ratio of the branching fractions for the ηc(1S) decays to φφ and p p as B(ηc(1S)→ φφ)/B(ηc(1S)→ p p) = 1.79 ± 0.14 ± 0.32. SI

A study of B0s → η c ϕ and B0s → η c π + π − decays is performed using pp collision data corresponding to an integrated luminosity of 3.0 fb−1, collected with the LHCb detector in Run 1 of the LHC. The observation of the decay B 0s → η c ϕ is reported, where the η c meson is reconstructed in the pp¯, K + K − π + π −, π + π − π + π − and K + K − K + K − decay modes and the ϕ(1020) in the K + K − decay mode. The decay B 0s → J/ψϕ is used as a normalisation channel. Evidence is also reported for the decay B 0s → η c π + π −, where the η c meson is reconstructed in the pp¯decay mode, using the decay B 0s → J/ψπ + π − as a normalisation channel. The measured branching fractions are B(B0s→ηcϕ)=(5.01±0.53±0.27±0.63)×10−4,B(B0s→ηcπ+π−)=(1.76±0.59±0.12±0.29)×10−4, where in each case the first uncertainty is statistical, the second systematic and the third uncertainty is due to the limited knowledge of the external branching fractions. SI

The polarization of the Y(1S), Y(2S) and Y(3S) mesons, produced in pp collisions at centre-of-mass energies √s=7 and 8 TeV, is measured using data samples collected by the LHCb experiment, corresponding to integrated luminosities of 1 and 2 fb−1, respectively. The measurements are performed in three polarization frames, using Y → μμ decays in the kinematic region of the transverse momentum p ΥT

The B0, B0s, B+ and Λ0b hadron production asymmetries are measured using a data sample corresponding to an integrated luminosity of 3.0fb−1, collected by the LHCb experiment in proton–proton collisions at centre-of-mass energies of 7 and 8TeV. The measurements are performed as a function of transverse momentum and rapidity of the bhadrons within the LHCb detector acceptance. The overall production asymmetries, integrated over transverse momentum and rapidity, are also determined. SI

A search for CPviolation in D±→η π±and D±s→η π±decays is performed using proton–proton collision data, corresponding to an integrated luminosity of 3fb−1, recorded by the LHCb experiment at centre-of-mass energies of 7and8TeV. The measured CP-violating charge asymmetries are ACP(D±→η π±) =(−0.61 ±0.72 ±0.53 ±0.12)%and ACP(D±s→η π±) =(−0.82 ±0.36 ±0.22 ±0.27)%, where the first uncertainties are statistical, the second systematic, and the third are the uncertainties on the ACP(D±→K0Sπ±)and ACP(D±s→φπ±)measurements used for calibration. The results represent the most precise measurements of these asymmetries to date. SI

A measurement is presented of decay-time-dependent CP violation in the decays B0 → J/ψ K 0S and B0 → ψ(2S)K 0S, where the J/ψ is reconstructed from two electrons and the ψ(2S) from two muons. The analysis uses a sample of pp collision data recorded with the LHCb experiment at centre-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb−1. The CP -violation observables are measured to be C(B0→J/ψK0S)=0.12±0.07±0.02,S(B0→J/ψK0S)=0.83±0.08±0.01,C(B0→ψ(2S)K0S)=−0.05±0.10±0.01,S(B0→ψ(2S)K0S)=0.84±0.10±0.01, where C describes CP violation in the direct decay, and S describes CP violation in the interference between the amplitudes for the direct decay and for the decay after B0−B¯0 oscillation. The first uncertainties are statistical and the second are systematic. The two sets of results are compatible with the previous LHCb measurement using B0 → J/ψ K 0S decays, where the J/ψ meson was reconstructed from two muons. The averages of all three sets of LHCb results are C(B0→[cc¯]K0S)=−0.017±0.029,S(B0→[cc¯]K0S)=0.760±0.034, under the assumption that higher-order contributions to the decay amplitudes are negligible. The uncertainties include statistical and systematic contributions. SI

The decays B+→J/ψ3π+2π− and B+→ψ(2S)π+π+π− are observed for the first time using a data sample corresponding to an integrated luminosity of 3.0 fb−1, collected by the LHCb experiment in proton–proton collisions at the centre-of-mass energies of 7 and 8TeV. The branching fractions relative to that of B+→ψ(2S)K+ are measured to be B(B+→J/ψ3π+2π−)B(B+→ψ(2S)K+)=B(B+→ψ(2S)π+π+π−)B(B+→ψ(2S)K+)=(1.88±0.17±0.09)×10−2,(3.04±0.50±0.26)×10−2, where the first uncertainties are statistical and the second are systematic. SI

A measurement of the production cross-section of Z bosons in pp collisions at √s=13 TeV is presented using dimuon and dielectron final states in LHCb data. The cross-section is measured for leptons with pseudorapidities in the range 2.0 < η < 4.5, transverse momenta p T > 20 GeV and dilepton invariant mass in the range 60 < m(ℓℓ) < 120 GeV. The integrated cross-section from averaging the two final states is σ ℓℓZ = 194.3 ± 0.9 ± 3.3 ± 7.6 pb, where the first uncertainty is statistical, the second is due to systematic effects, and the third is due to the luminosity determination. In addition, differential cross-sections are measured as functions of the Z boson rapidity, transverse momentum and the angular variable ϕ *η. SI

The decays Λ0b → ψ(2S)pK− and Λ0b → J/ψπ + π −pK− are observed in a data sample corresponding to an integrated luminosity of 3 fb−1, collected in proton-proton collisions at 7 and 8 TeV centre-of-mass energies by the LHCb detector. The ψ(2S) mesons are reconstructed through the decay modes ψ(2S) → μ+μ− and ψ(2S) → J/ψπ + π −. The branching fractions relative to that of Λ0b → J/ψpK− are measured to be B(Λ0b→ψ(2S)pK−)B(Λ0b→J/ψpK−)=(20.70±0.76±0.46±0.37)×10−2, where the first uncertainties are statistical, the second are systematic and the third is related to the knowledge of J/ψ and ψ(2S) branching fractions. The mass of the Λ 0b baryon is measured to be M(Λ0b)=5619.65±0.17±0.17 MeV/c2, where the uncertainties are statistical and systematic. SI

The Λ0b→Λφdecay is observed using data corresponding to an integrated luminosity of 3.0fb−1recorded by the LHCbexperiment. The decay proceeds at leading order via a b →sssloop transition and is therefore sensitive to the possible presence of particles beyond the Standard Model. A first observation is reported with a significance of 5.9standard deviations. The value of the branching fraction is measured to be (5.18 ±1.04 ±0.35+0.67−0.62) ×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. SI

Two-particle angular correlations are studied in proton-lead collisions at a nucleon–nucleon centre-of-mass energy of √sNN=5TeV, collected with the LHCb detector at the LHC. The analysis is based on data recorded in two beam configurations, in which either the direction of the proton or that of the lead ion is analysed. The correlations are measured in the laboratory system as a function of relative pseudorapidity, η, and relative azimuthal angle, φ, for events in different classes of event activity and for different bins of particle transverse momentum. In high-activity events a long-range correlation on the near side, φ≈0, is observed in the pseudorapidity range 2.0