Showing papers by "Gianni Penso published in 2012"
TL;DR: In this article, the ratio of meson to light meson production with respect to the transverse momentum of the charmed hadron-muon pair has been investigated at a center-of-mass energy of 7 TeV with an integrated luminosity of 3 pb$-1.
Abstract: Measurements of $b$ hadron production ratios in proton-proton collisions at a centre-of-mass energy of 7 TeV with an integrated luminosity of 3 pb$^{-1}$ are presented. We study the ratios of strange $B$ meson to light $B$ meson production $f_s/(f_u+f_d)$ and $Lambda_b^0$ baryon to light $B$ meson production $f_{Lambda_b}/(f_u+f_d)$ as a function of the charmed hadron-muon pair transverse momentum $p_T$ and the $b$ hadron pseudorapidity $eta$, for $p_T$ between 0 and 14 GeV and $eta$ between 2 and 5. We find that $f_s/(f_u+f_d)$ is consistent with being independent of $p_{rm T}$ and $eta$, and we determine $f_s/(f_u+f_d)$ = 0.134$pm$ 0.004 $^{+0.011}_{-0.010}$, where the first error is statistical and the second systematic. The corresponding ratio $f_{Lambda_b}/(f_u+f_d)$ is found to be dependent upon the transverse momentum of the charmed hadron-muon pair, $f_{Lambda_b}/(f_u+f_d)=(0.404pm 0.017 (stat) pm 0.027 (syst) pm 0.105 (Br))times[1 -(0.031 pm 0.004 (stat) pm 0.003 (syst))times p_T(GeV)]$, where Br reflects an absolute scale uncertainty due to the poorly known branching fraction Br(Lambda_c^+ to pK^-pi^+)$. We extract the ratio of strange $B$ meson to light neutral $B$ meson production $f_s/f_d$ by averaging the result reported here with two previous measurements derived from the relative abundances of $bar{B}_s to D_S^+ pi ^-$ to $bar{B}^0 to D^+K^-$ and $bar{B}^0 to D^+pi^-$. We obtain $f_s/f_d=0.267^{+0.021}_{-0.020}$.
254 citations
TL;DR: In this article, a search for Bs0→μ+μ- and B0→m+m- decays was performed using 1.0 fb-1 of pp collision data collected at √s=7 TeV with the LHCb experiment at the Large Hadron Collider.
Abstract: A search for Bs0→μ+μ- and B0→μ+μ- decays is performed using 1.0 fb-1 of pp collision data collected at √s=7 TeV with the LHCb experiment at the Large Hadron Collider. For both decays, the number of observed events is consistent with expectation from background and standard model signal predictions. Upper limits on the branching fractions are determined to be B(Bs0→μ+μ-)<4.5(3.8)×10-9 and B(B0→μ+μ-)<1.0(0.81)×10-9 at 95% (90%) confidence level.
237 citations
TL;DR: The production of J/psi mesons accompanied by open charm, and of pairs of open charm hadrons are observed in pp collisions at a centre-of-mass energy of 7 TeV using an integrated luminosity of 355 pb(-1) collected with the LHCb detector as mentioned in this paper.
Abstract: The production of J/psi mesons accompanied by open charm, and of pairs of open charm hadrons are observed in pp collisions at a centre-of-mass energy of 7 TeV using an integrated luminosity of 355 pb(-1) collected with the LHCb detector. Model independent measurements of absolute cross-sections are given together with ratios to the measured J/psi and open charm cross-sections. The properties of these events are studied and compared to theoretical predictions.
155 citations
TL;DR: In this paper, the production of $J/\psi$ pairs in proton-proton collisions at a center-of-mass energy of 7 TeV has been observed using an integrated luminosity of $37.5 pb^{-1}$ collected with the LHCb detector.
151 citations
TL;DR: In this article, a discovery of the rare decay $B^{+} \rightarrow \pi+} √ K+ √ √ N+ \K+ \mu+} − √ n − 1.
Abstract: A discovery of the rare decay $B^{+} \rightarrow \pi^{+} \mu^{+} \mu^{-}$ is presented. This decay is observed for the first time, with 5.2 $\sigma$ significance. The observation is made using $pp$ collision data, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected with the LHCb detector. The measured branching fraction is (2.3 $\pm$ 0.6 (stat.) $\pm$ 0.1 (syst.))$\times 10^{-8}$, and the ratio of the $B^{+} \rightarrow \pi^{+} \mu^{+} \mu^{-}$ and $B^{+} \rightarrow \K^{+} \mu^{+} \mu^{-}$ branching fractions is measured to be 0.053 $\pm$ 0.014 (stat.) $\pm$ 0.001 (syst.).
151 citations
TL;DR: In this paper, the decay time distribution of B_s -> J/psi phi is characterized by the decay widths Gamma_H and Gamma_L of the heavy and light mass eigenstates of the B_S-B_s-bar system and by a CP-violating phase phi_s.
Abstract: We present a measurement of the time-dependent CP-violating asymmetry in B_s -> J/psi phi decays, using data collected with the LHCb detector at the LHC. The decay time distribution of B_s -> J/psi phi is characterized by the decay widths Gamma_H and Gamma_L of the heavy and light mass eigenstates of the B_s-B_s-bar system and by a CP-violating phase phi_s. In a sample of about 8500 B_s -> J/psi phi events isolated from 0.37 fb^-1 of pp collisions at sqrt(s)=7 TeV we measure phi_s = 0.15 +/- 0.18 (stat) +/- 0.06 (syst) rad. We also find an average B_s decay width Gamma_s == (Gamma_L + Gamma_H)/2 = 0.657 +/- 0.009 (stat) +/- 0.008 (syst) ps^-1 and a decay width difference Delta Gamma_s == Gamma_L - Gamma_H} = 0.123 +/- 0.029 (stat) +/- 0.011 (syst) ps^-1. Our measurement is insensitive to the transformation (phi_s,DeltaGamma_s --> pi - phi_s, - Delta Gamma_s.
124 citations
TL;DR: The calibration and performance of the opposite-side flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described.
Abstract: The calibration and performance of the opposite-side flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B+→J/ψK+, B0→J/ψK∗0 and B0→D∗−μ+νμ decay modes with 0.37 fb−1 of data collected in pp collisions at \(\sqrt{s} = 7\mbox{~TeV}\) during the 2011 physics run. The opposite-side tagging power is determined in the B+→J/ψK+ channel to be (2.10±0.08±0.24) %, where the first uncertainty is statistical and the second is systematic.
106 citations
TL;DR: It is concluded that the B(s)(0) mass eigenstate that is almost CP = +1 is lighter and decays faster than themass eigen state that isalmost CP = -1, which resolves the ambiguity in the past measurements of the CP violating phase ϕ(s) to be close to zero rather than π.
Abstract: The interference between the K+K- S-wave and P-wave amplitudes in B_s -> J/psi K+K- decays with the K+K- pairs in the region around the phi(1020) resonance is used to determine the variation of the difference of the strong phase between these amplitudes as a function of K+K- invariant mass. Combined with the results from our CP asymmetry measurements in B_s -> J/psi phi decays, we conclude that the B_s mass eigenstate that is almost CP =+1 is lighter and decays faster than the mass eigenstate that is almost CP =-1. This determines the sign of the decay width difference DeltaGamma_s == Gamma_L -Gamma_H to be positive. Our result also resolves the ambiguity in the past measurements of the CP violating phase phi_s to be close to zero rather than pi. These conclusions are in agreement with the Standard Model expectations.
103 citations
TL;DR: In this paper, the angular distribution and differential branching fraction of the decay B 0→K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1.
Abstract: The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions.
100 citations
TL;DR: In this article, two narrow states are observed in the Lambda_b0pi+pi- spectrum with masses 5911.95 +- 0.12(stat) + − 0.03(syst) + - 0.76 +-0.07(stat), +-
Abstract: Using pp collision data corresponding to 1.0 fb-1 integrated luminosity collected by the LHCb detector, two narrow states are observed in the Lambda_b0pi+pi- spectrum with masses 5911.95 +- 0.12(stat) +- 0.03(syst) +- 0.66(Lambda_b0 mass) MeV/c^2 and 5919.76 +- 0.07(stat) +- 0.02(syst) +- 0.66(Lambda_b0 mass) MeV/c^2. The significances of the observations are 4.9 and 10.1 standard deviations, respectively. These states are interpreted as the orbitally-excited Lambda_b0 baryons, Lambda_b*0(5912) and Lambda_b*0(5920).
99 citations
TL;DR: In this article, the W and Z boson production cross-sections in p p collisions at root s = 7TeV using final states containing muons are measured using the LHCb detector.
Abstract: Measurements of inclusive W and Z boson production cross-sections in p p collisions at root s = 7TeV using final states containing muons are presented. The data sample corresponds to an integrated luminosity of 37 pb(-1) collected with the LHCb detector. The W and Z bosons are reconstructed from muons with a transverse momentum above 20 GeV/c and pseudorapidity between 2.0 and 4.5, and, in the case of the Z cross-section, a dimuon invariant mass between 60 and 120 GeV/c(2). The cross-sections are measured to be 831 +/- 9 +/- 27 +/- 29 pb for W+, 656 +/- 8 +/- 19 +/- 23 for W- and 76.7 +/- 1.7 +/- 3.3 +/- 2.7 pb for Z, where the first uncertainty is statistical, the second is systematic and the third is due to the luminosity. Differential cross-sections, W and Z cross-section ratios and the lepton charge asymmetry are also measured in the same kinematic region. The ratios are determined to be sigma W+->mu(+)nu/sigma W-->mu-(nu) over bar = 1.27 +/- 0.02 +/- 0.01 and (sigma W+->mu+nu+sigma W-->mu-(nu) over bar)/sigma Z ->mu mu = 19.4 +/- 0.5 +/- 0.9. The results are in general agreement with theoretical predictions, performed at next-to-next-to-leading order in QCD using recently calculated parton distribution functions.
TL;DR: In this paper, the authors measured B-c(+) production and mass with the decay mode Bc(c++) -> J/psi pi(+) using 0.37 fb(-1) of data collected in pp collisions at root s = 7 TeV by the LHCb experiment.
Abstract: Measurements of B-c(+) production and mass are performed with the decay mode B-c(+) -> J/psi pi(+) using 0.37 fb(-1) of data collected in pp collisions at root s = 7 TeV by the LHCb experiment. The ratio of the production cross section times branching fraction between the B-c(+) -> J/psi pi(+) and the B+ -> J/psi K+ decays is measured to be (0.68 +/- 0.10(stat) +/- 0.03(syst) +/- 0.05(lifetime))% for B-c(+) and B+ mesons with transverse momenta p(T) > 4 GeV/c and pseudorapidities 2.5 < eta < 4.5. The B-c(+) mass is directly measured to be 6273.7 +/- 1.3(stat) +/- 1.6(syst) MeV/c(2), and the measured mass difference with respect to the B+ meson is M(B-c(+)) - M(B+) = 994.6 +/- 1.3(stat) +/- 0.6(syst) MeV/c(2).
TL;DR: In this paper, the authors studied the production of ϒ(1S), ϒ (2S) and ϒ-(3S) mesons in proton-proton collisions at the centre-of-mass energy of [Formula: see text] is studied with the LHCb detector.
Abstract: The production of ϒ(1S), ϒ(2S) and ϒ(3S) mesons in proton-proton collisions at the centre-of-mass energy of [Formula: see text] is studied with the LHCb detector. The analysis is based on a data sample of 25 pb-1 collected at the Large Hadron Collider. The ϒ mesons are reconstructed in the decay mode ϒ→μ+μ- and the signal yields are extracted from a fit to the μ+μ- invariant mass distributions. The differential production cross-sections times dimuon branching fractions are measured as a function of the ϒ transverse momentum pT and rapidity y, over the range pT <15 GeV/c and 2.0
TL;DR: In this article, the authors measured the isospin asymmetries of B-0-K-s(0)mu(+)mu(-) with an integrated luminosity of 1.0 fb(-1) collected with the LHCb detector.
Abstract: The isospin asymmetries of B -> K-(*)mu(+)mu(-) decays and the partial branching fractions of B-0 -> K-0 mu(+)mu(-) and B+ -> K*+mu(+)mu(-) are measured as a function of the di-muon mass squared q(2) using an integrated luminosity of 1.0 fb(-1) collected with the LHCb detector. The B -> K mu(+)mu(-) isospin asymmetry integrated over q(2) is negative, deviating from zero with over 4 sigma significance. The B -> K*mu(+)mu(-) decay measurements are consistent with the Standard Model prediction of negligible isospin asymmetry. The observation of the decay B0 -> K-s(0)mu(+)mu(-) is reported with 5.7 sigma significance. Assuming that the branching fraction of B-0 -> K-0 mu(+)mu(-) is twice that of B-0 -> K-s(0)mu(+)mu(-), the branching fractions of B-0 -> K-0 mu(+)mu(-) and B -> K*(+)mu(+)mu(-) it are found to be (0.31(-0.06)(+0.07)) x 10(-6) and (1.16 +/- 0.19) x 10(-6), respectively.
TL;DR: In this article, a modified Dalitz-plot analysis is performed using both the invariant mass spectra and the decay angular distributions, leading to an upper limit on the absolute value of the mixing angle of the fₒ(980) with the f∆(500) of less than 31°, both at 90% confidence level.
Abstract: Interpretation of CP violation measurements using charmonium decays, in both the B¯o and B¯os systems, can be subject to changes due to "penguin" type diagrams. These effects can be investigated using measurements of the Cabibbo-suppressed B¯o → J/ ψπ+π- decays. The final state composition of this channel is investigated using a 1.0 fb(-1) sample of data produced in 7 TeV pp collisions at the LHC and collected by the LHCb experiment. A modified Dalitz-plot analysis is performed using both the invariant mass spectra and the decay angular distributions. An improved measurement of the B¯o → J/ ψπ+π- branching fraction of (3.97 ± 0.09 ± 0.11 ± 0.16) x 10(-5) is reported where the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty of the branching fraction of the decay B¯ → J/ ψ K¯ used as a normalization channel. Significant production of fₒ(500) and ρ(770) resonances is found in the substructure of the J/ ψπ+π- final state, and this indicates that they are viable final states for CP violation studies. In contrast evidence for the fₒ(980) resonance is not found. This allows us to establish the first upper limit on the branching fraction product Β(B¯o → J/ ψfₒ (980)) x Β(fₒ(980) → π+π- < 1.1 x 10(-6), leading to an upper limit on the absolute value of the mixing angle of the fₒ(980) with the fₒ(500) of less than 31°, both at 90% confidence level.
TL;DR: In this article, searches for heavy Majorana neutrinos in B-decays in final states containing hadrons plus a \mu- \mu − pair have been performed using 0.41/fb of data collected with the LHCb detector in proton-proton collisions at a center-of-mass energy of 7 TeV.
Abstract: Searches for heavy Majorana neutrinos in B- decays in final states containing hadrons plus a \mu- \mu- pair have been performed using 0.41/fb of data collected with the LHCb detector in proton-proton collisions at a center-of-mass energy of 7 TeV. The D+ \mu- \mu- and D*+ \mu- \mu- final states can arise from the presence of virtual Majorana neutrinos of any mass. Other final states containing \pi+, Ds+, or D0\pi+ can be mediated by an on-shell Majorana neutrino. No signals are found and upper limits are set on Majorana neutrino production as a function of mass, and also on the B- decay branching fractions.
TL;DR: In this article, the decay mode Bs -> pi+pi- is observed for the first time with a significance of more than 5 sigma, where the first uncertainties are statistical and the second systematic.
Abstract: Based on data corresponding to an integrated luminosity of 0.37 fb^-1 collected by the LHCb experiment in 2011, the following ratios of branching fractions are measured: B(B0 -> pi+ pi-) / B(B0 -> K+pi-) = 0.262 +/- 0.009 +/- 0.017, (fs/fd) * B(Bs -> K+K-) / B(B^0 -> K+pi-) = 0.316 +/- 0.009 +/- 0.019, (fs/fd) * B(Bs ->pi+ K-) / B(B0 -> K+pi-) = 0.074 +/- 0.006 +/- 0.006, (fd/fs) * B(B0 -> K+K-) / B(Bs -> K+K-) = 0.018 {+ 0.008 - 0.007} +/- 0.009, (fs/fd) * B(Bs -> pi+pi-) / B(B0 -> pi+pi-) = 0.050 {+ 0.011 - 0.009} +/- 0.004, B(Lambda_b -> p pi-) / B(Lambda_b -> p K-) = 0.86 +/- 0.08 +/- 0.05, where the first uncertainties are statistical and the second systematic. Using the current world average of B(B0 -> K+pi-) and the ratio of the strange to light neutral B meson production fs/fd measured by LHCb, we obtain: B(B0 -> pi+pi-) = (5.08 +/- 0.17 +/- 0.37) x 10^-6, B(Bs -> K+K-) = (23.0 +/- 0.7 +/- 2.3) x 10^-6, B(Bs -> pi+K-) = (5.4 +/- 0.4 +/- 0.6) x 10^-6, B(B0 -> K+K-) = (0.11 {+ 0.05 - 0.04} +/- 0.06) x 10^-6, B(Bs -> pi+pi-) = (0.95 {+ 0.21 - 0.17} +/- 0.13) x 10^-6. The measurements of B(Bs -> K+K-), B(Bs -> pi+ K-) and B(B0 -> K+K-) are the most precise to date. The decay mode Bs -> pi+pi- is observed for the first time with a significance of more than 5 sigma.
TL;DR: In this paper, b-hadron masses were measured with the exclusive decay modes B+ -> J/\psi\ K+, B0-> J/ \psi/ K*0, B0s, B1s, and B2s with an integrated luminosity of 35 pb-1 collected in pp collisions at a centre-of-mass energy of 7 TeV.
TL;DR: In this article, the prompt production of the charmonium mesons was studied in proton-proton collisions at the Large Hadron Collider at a centre-of-mass energy of 7$ TeV.
TL;DR: In this article, the decay of Bc+→J/ψπ+π-π++π+ is observed for the first time, using 0.8 ǫfb-1 of pp collisions at √s=7 ÃǫTeV collected by the LHCb experiment.
Abstract: The decay Bc+→J/ψπ+π-π+ is observed for the first time, using 0.8 fb-1 of pp collisions at √s=7 TeV collected by the LHCb experiment. The ratio of branching fractions B(Bc+→J/ψπ+π-π+)/B(Bc+→J/ψπ+) is measured to be 2.41±0.30±0.33, where the first uncertainty is statistical and the second is systematic. The result is in agreement with theoretical predictions.
TL;DR: In this article, the differential cross-section for the inclusive production of psi(2S) mesons in pp collisions at sqrt(s)=7 TeV has been measured with the LHCb detector.
Abstract: The differential cross-section for the inclusive production of psi(2S) mesons in pp collisions at sqrt(s)=7 TeV has been measured with the LHCb detector. The data sample corresponds to an integrated luminosity of 36 pb-1. The psi(2S) mesons are reconstructed in the decay channels psi(2S) -> mu+ mu- and psi(2S) -> J/psi pi+ pi-, with the J/psi meson decaying into two muons. Results are presented both for promptly produced psi(2S) mesons and for those originating from b-hadron decays. In the kinematic range pT(psi(2S)) psi(2S) X) = (2.73 +- 0.06 +- 0.16 +- 0.24) x 10^(-3), where the last uncertainty is due to the B(b -> J/psi X), B(J/psi -> mu+ mu-) and B(psi(2S) -> e+ e-) branching fraction uncertainties.
TL;DR: In this paper, a search for the X(4140) state in B+ to J/psi phi K+ decays is performed with 0.37 fb-1 of pp collisions at sqrt(s)=7 TeV collected by the LHCb experiment.
Abstract: A search for the X(4140) state in B+ to J/psi phi K+ decays is performed with 0.37 fb-1 of pp collisions at sqrt(s)=7 TeV collected by the LHCb experiment. No evidence for this state is found, in 2.4 sigma disagreement with a measurement by CDF. An upper limit on its production rate is set, BR(B+ to X(4140) K+) BR(X(4140) to J/psi phi) / BR(B+ to J/psi phi K+) < 0.07 at 90% confidence level.
TL;DR: In this paper, the B-s(0)-(B) over bar (0) oscillation frequency Delta m(s) is measured with 36 pb(-1) of data collected in pp collisions at = 7 TeV by the LHCb experiment at the Large Hadron Collider.
TL;DR: In this article, the charged particle production in proton-proton collisions is studied with the LHCb detector at a centre-of-mass energy of ${\sqrt{s} =7}$TeV in different intervals of pseudorapidity.
Abstract: The charged particle production in proton-proton collisions is studied with the LHCb detector at a centre-of-mass energy of ${\sqrt{s} =7}$TeV in different intervals of pseudorapidity $\eta$. The charged particles are reconstructed close to the interaction region in the vertex detector, which provides high reconstruction efficiency in the $\eta$ ranges $-2.5<\eta<-2.0$ and $2.0<\eta<4.5$. The data were taken with a minimum bias trigger, only requiring one or more reconstructed tracks in the vertex detector. By selecting an event sample with at least one track with a transverse momentum greater than 1 GeV/c a hard QCD subsample is investigated. Several event generators are compared with the data; none are able to describe fully the multiplicity distributions or the charged particle density distribution as a function of $\eta$. In general, the models underestimate the charged particle production.
TL;DR: In this paper, a search for the lepton number violating decay with respect to the Majorana neutrino was performed using data from the LHCb detector corresponding to an integrated luminosity of 36pb^{-1}.
Abstract: A search is performed for the lepton number violating decay $B^{+}\rightarrow h^- \mu^+ \mu^+$, where $h^-$ represents a $K^-$ or a $\pi^-$, using data from the LHCb detector corresponding to an integrated luminosity of $36pb^{-1}$. The decay is forbidden in the Standard Model but allowed in models with a Majorana neutrino. No signal is observed in either channel and limits of $B(B^{+} \rightarrow K^- \mu^+ \mu^+) < 5.4\times 10^{-8}$ and $B(B^{+} \rightarrow \pi^- \mu^+ \mu^+) < 5.8\times 10^{-8}$ are set at the 95% confidence level. These improve the previous best limits by factors of 40 and 30, respectively.
TL;DR: In this article, a study of mixing and indirect CP violation in D-0 mesons through the determination of the parameters y(CP) and A(Gamma) is presented.
Abstract: A study of mixing and indirect CP violation in D-0 mesons through the determination of the parameters y(CP) and A(Gamma) is presented. The parameter y(CP) is the deviation from unity of the ratio of effective lifetimes measured in D-0 decays to the CP eigenstate K+K- with respect to decays to the Cabibbo favoured mode K-pi(+). The result measured using data collected by LHCb in 2010, corresponding to an integrated luminosity of 29 pb(-1), is y(CP) = (5.5 +/- 6.3(stat) +/- 4.1(syst)) x 10(-3). The parameter A(Gamma) is the asymmetry of effective lifetimes measured in decays of D-0 and (D) over bar (0) mesons to K+K-. The result is A = (-5.9 +/- 5.9(stat) +/- 2.1(syst)) x 10(-3). A data-driven technique is used to correct for lifetime-biasing effects.
TL;DR: In this article, a measurement using an LHCb data sample of 0.41 fb(-1), in the CP odd eigenstate J/psi f(0)(980), where f( 0)(980) → pi(+)pi(-), is presented.
TL;DR: In this paper, the LHCb detector was used to measure the charged particle production ratio, which is a function of transverse momentum and pseudorapidity, and was compared to several Monte Carlo generator settings.
Abstract: The charged-particle production ratios $\bar{p}/p$, $K^-/K^+$, $\pi^-/\pi^+$, $(p + \bar{p})/(\pi^+ + \pi^-)$, $(K^+ + K^-)/(\pi^+ + \pi^-)$ and $(p + \bar{p})/(K^+ + K^-)$ are measured with the LHCb detector using $0.3\,{\rm nb^{-1}}$ of $pp$ collisions delivered by the LHC at $\sqrt{s} = 0.9$ TeV and $1.8\,{\rm nb^{-1}}$ at $\sqrt{s} = 7$ TeV. The measurements are performed as a function of transverse momentum $p_{\rm T}$ and pseudorapidity $\eta$. The production ratios are compared to the predictions of several Monte Carlo generator settings, none of which are able to describe adequately all observables. The ratio $\bar{p}/p$ is also considered as a function of rapidity loss, $\Delta y \equiv y_{\rm beam} - y$, and is used to constrain models of baryon transport.
TL;DR: In this article, a binned Dalitz plot analysis is performed to measure the CP-violating observables, which are sensitive to the CKM angle, using measurements of this quantity from CLEO-c as input.
TL;DR: The relative rates of B-meson decays into J/ψ and ψ(2S) mesons are measured for the three decay modes in pp collisions recorded with the LHCb detector to measure the ratios of branching fractions.
Abstract: The relative rates of B-meson decays into $J/\psi$ and $\psi(2S)$ mesons are measured for the three decay modes in pp collisions recorded with the LHCb detector. The ratios of branching fractions ($\mathcal{B}$) are measured to be \frac{\mathcal{B}(B^+ \to \psi(2S) K^+)}{\mathcal{B}(B^+ \to J/\psi K^+)} &=& 0.594 \pm 0.006 (stat) \pm 0.016 (syst) \pm 0.015 (R_{\psi}), \frac{\mathcal{B}(B^0 \to \psi(2S) K^{*0})}{\mathcal{B}(B^0 \to J/\psi K^{*0})} &=& 0.476 \pm 0.014 (stat) \pm 0.010 (syst) \pm 0.012\,(R_{\psi}), \frac{\mathcal{B}^{0}_{s}(B^0_s \to \psi(2S)\phi)}{\mathcal{B}(B^0_s \to J/\psi\phi)} &=& 0.489 \pm 0.026 (stat) \pm 0.021 (syst) \pm 0.012\,(R_{\psi}) where the third uncertainty is from the ratio of the $\psi(2S)$ and $J/\psi$ branching fractions to $\mumu$.