70 research outputs found

    Measurement of the (eta c)(1S) production cross-section in proton-proton collisions via the decay (eta c)(1S) -> p(p)over-bar

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    The production of the ηc(1S)\eta_c (1S) state in proton-proton collisions is probed via its decay to the ppˉp \bar{p} final state with the LHCb detector, in the rapidity range 2.06.52.0 6.5 GeV/c. The cross-section for prompt production of ηc(1S)\eta_c (1S) mesons relative to the prompt J/ψJ/\psi cross-section is measured, for the first time, to be σηc(1S)/σJ/ψ=1.74±0.29±0.28±0.18B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.74 \pm 0.29 \pm 0.28 \pm 0.18 _{B} at a centre-of-mass energy s=7\sqrt{s} = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb1^{-1}, and σηc(1S)/σJ/ψ=1.60±0.29±0.25±0.17B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.60 \pm 0.29 \pm 0.25 \pm 0.17 _{B} at s=8\sqrt{s} = 8 TeV using 2.0 fb1^{-1}. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the ηc(1S)\eta_c (1S) and J/ψJ/\psi decays to the ppˉp \bar{p} final state. In addition, the inclusive branching fraction of bb-hadron decays into ηc(1S)\eta_c (1S) mesons is measured, for the first time, to be B(bηcX)=(4.88±0.64±0.25±0.67B)×103B ( b \rightarrow \eta_c X ) = (4.88 \pm 0.64 \pm 0.25 \pm 0.67 _{B}) \times 10^{-3}, where the third uncertainty includes also the uncertainty on the J/ψJ/\psi inclusive branching fraction from bb-hadron decays. The difference between the J/ψJ/\psi and ηc(1S)\eta_c (1S) meson masses is determined to be 114.7±1.5±0.1114.7 \pm 1.5 \pm 0.1 MeV/c2^2.The production of the ηc(1S)\eta _c (1S) state in proton-proton collisions is probed via its decay to the ppp\overline{p} final state with the LHCb detector, in the rapidity range 2.06.5GeV/c2.0 6.5 \mathrm{{\,GeV/}{ c}} . The cross-section for prompt production of ηc(1S)\eta _c (1S) mesons relative to the prompt J/ψ{{ J}}/{\psi } cross-section is measured, for the first time, to be σηc(1S)/σJ/ψ=1.74±0.29±0.28±0.18B\sigma _{\eta _c (1S)}/\sigma _{{{{ J}}/{\psi }}} = 1.74\, \pm \,0.29\, \pm \, 0.28\, \pm \,0.18 _{{\mathcal{B}}} at a centre-of-mass energy s=7 TeV{\sqrt{s}} = 7 {~\mathrm{TeV}} using data corresponding to an integrated luminosity of 0.7 fb1^{-1} , and σηc(1S)/σJ/ψ=1.60±0.29±0.25±0.17B\sigma _{\eta _c (1S)}/\sigma _{{{{ J}}/{\psi }}} = 1.60 \pm 0.29 \pm 0.25 \pm 0.17 _{{\mathcal{B}}} at s=8 TeV{\sqrt{s}} = 8 {~\mathrm{TeV}} using 2.0 fb1^{-1} . The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the ηc(1S)\eta _c (1S) and J/ψ{{ J}}/{\psi } decays to the ppp\overline{p} final state. In addition, the inclusive branching fraction of b{b} -hadron decays into ηc(1S)\eta _c (1S) mesons is measured, for the first time, to be B(bηcX)=(4.88±0.64±0.29±0.67B)×103{\mathcal{B}}( b {\rightarrow } \eta _c X ) = (4.88\, \pm \,0.64\, \pm \,0.29\, \pm \, 0.67 _{{\mathcal{B}}}) \times 10^{-3} , where the third uncertainty includes also the uncertainty on the J/ψ{{ J}}/{\psi } inclusive branching fraction from b{b} -hadron decays. The difference between the J/ψ{{ J}}/{\psi } and ηc(1S)\eta _c (1S) meson masses is determined to be 114.7±1.5±0.1MeV ⁣/c2114.7 \pm 1.5 \pm 0.1 {\mathrm {\,MeV\!/}c^2} .The production of the ηc(1S)\eta_c (1S) state in proton-proton collisions is probed via its decay to the ppˉp \bar{p} final state with the LHCb detector, in the rapidity range 2.06.52.0 6.5 GeV/c. The cross-section for prompt production of ηc(1S)\eta_c (1S) mesons relative to the prompt J/ψJ/\psi cross-section is measured, for the first time, to be σηc(1S)/σJ/ψ=1.74±0.29±0.28±0.18B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.74 \pm 0.29 \pm 0.28 \pm 0.18 _{B} at a centre-of-mass energy s=7\sqrt{s} = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb1^{-1}, and σηc(1S)/σJ/ψ=1.60±0.29±0.25±0.17B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.60 \pm 0.29 \pm 0.25 \pm 0.17 _{B} at s=8\sqrt{s} = 8 TeV using 2.0 fb1^{-1}. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the ηc(1S)\eta_c (1S) and J/ψJ/\psi decays to the ppˉp \bar{p} final state. In addition, the inclusive branching fraction of bb-hadron decays into ηc(1S)\eta_c (1S) mesons is measured, for the first time, to be B(bηcX)=(4.88±0.64±0.29±0.67B)×103B ( b \rightarrow \eta_c X ) = (4.88 \pm 0.64 \pm 0.29 \pm 0.67 _{B}) \times 10^{-3}, where the third uncertainty includes also the uncertainty on the J/ψJ/\psi inclusive branching fraction from bb-hadron decays. The difference between the J/ψJ/\psi and ηc(1S)\eta_c (1S) meson masses is determined to be 114.7±1.5±0.1114.7 \pm 1.5 \pm 0.1 MeV/c2^2

    Search for the lepton flavour violating decay tau(-) -> mu(-)mu(+)mu(-)

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    A search for the lepton flavour violating decay τμμ+μ\tau^-\rightarrow\mu^-\mu^+\mu^- is performed with the LHCb experiment. The data sample corresponds to an integrated luminosity of 1.0 fb1^{−1} of proton-proton collisions at a centre-of-mass energy of 7 TeV and 2.0 fb1^{−1} at 8 TeV. No evidence is found for a signal, and a limit is set at 90% confidence level on the branching fraction, B(τμμ+μ)<4.6×108\mathcal{B}(\tau^-\rightarrow\mu^-\mu^+\mu^-)<4.6\times10^{−8}.A search for the lepton flavour violating decay τ^{−} → μ^{−} μ+^{+} μ^{−} is performed with the LHCb experiment. The data sample corresponds to an integrated luminosity of 1.0 fb1^{−1} of proton-proton collisions at a centre-of-mass energy of 7 TeV and 2.0 fb1^{−1} at 8 TeV. No evidence is found for a signal, and a limit is set at 90% confidence level on the branching fraction, B(τμμ+μ)<4.6×108 \mathrm{\mathcal{B}}\left({\tau}^{-}\to {\mu}^{-}{\mu}^{+}{\mu}^{-}\right)<4.6\times {10}^{-8} .A search for the lepton flavour violating decay τμμ+μ\tau^-\to \mu^-\mu^+\mu^- is performed with the LHCb experiment. The data sample corresponds to an integrated luminosity of 1.0fb11.0\mathrm{\,fb}^{-1} of proton-proton collisions at a centre-of-mass energy of 7TeV7\mathrm{\,Te\kern -0.1em V} and 2.0fb12.0\mathrm{\,fb}^{-1} at 8TeV8\mathrm{\,Te\kern -0.1em V}. No evidence is found for a signal, and a limit is set at 90%90\% confidence level on the branching fraction, B(τμμ+μ)<4.6×108\mathcal{B}(\tau^-\to \mu^-\mu^+\mu^-) < 4.6 \times 10^{-8}

    Search for CP violation using T-odd correlations in D-0 -&gt; K+K-pi(+)pi(-) decays

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    A search for CPCP violation using TT-odd correlations is performed using the four-body D0K+Kπ+πD^0 \to K^+K^-\pi^+\pi^- decay, selected from semileptonic BB decays. The data sample corresponds to integrated luminosities of 1.0fb11.0\,\text{fb}^{-1} and 2.0fb12.0\,\text{fb}^{-1} recorded at the centre-of-mass energies of 7 TeV and 8 TeV, respectively. The CPCP-violating asymmetry aCPT-odda_{CP}^{T\text{-odd}} is measured to be (0.18±0.29(stat)±0.04(syst))%(0.18\pm 0.29\text{(stat)}\pm 0.04\text{(syst)})\%. Searches for CPCP violation in different regions of phase space of the four-body decay, and as a function of the D0D^0 decay time, are also presented. No significant deviation from the CPCP conservation hypothesis is found

    Measurement of CP asymmetry in B-s(0) -&gt; D-s(-/+) K--/+ decays

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    We report on measurements of the time-dependent CP violating observables in Bs0DsK±B^0_s\rightarrow D^{\mp}_s K^{\pm} decays using a dataset corresponding to 1.0 fb1^{-1} of pp collisions recorded with the LHCb detector. We find the CP violating observables Cf=0.53±0.25±0.04C_f=0.53\pm0.25\pm0.04, AfΔΓ=0.37±0.42±0.20A^{\Delta\Gamma}_f=0.37\pm0.42\pm0.20, AfˉΔΓ=0.20±0.41±0.20A^{\Delta\Gamma}_{\bar{f}}=0.20\pm0.41\pm0.20, Sf=1.09±0.33±0.08S_f=-1.09\pm0.33\pm0.08, Sfˉ=0.36±0.34±0.08S_{\bar{f}}=-0.36\pm0.34\pm0.08, where the uncertainties are statistical and systematic, respectively. We use these observables to make the first measurement of the CKM angle γ\gamma in Bs0DsK±B^0_s\rightarrow D^{\mp}_s K^{\pm} decays, finding γ\gamma = (11543+28_{-43}^{+28})^\circ modulo 180^\circ at 68% CL, where the error contains both statistical and systematic uncertainties.We report on measurements of the time-dependent CP violating observables in Bs0_{s}^{0}  → Ds_{s}^{∓} K±^{±} decays using a dataset corresponding to 1.0 fb1^{−1} of pp collisions recorded with the LHCb detector. We find the CP violating observables Cf_{f} = 0.53±0.25±0.04, AfΔΓ_{f}^{ΔΓ}  = 0.37 ± 0.42 ± 0.20, AfΔΓ=0.20±0.41±0.20 {A}_{\overline{f}}^{\varDelta \varGamma }=0.20\pm 0.41\pm 0.20 , Sf_{f} = −1.09±0.33±0.08, Sf=0.36±0.34±0.08 {S}_{\overline{f}}=-0.36\pm 0.34\pm 0.08 , where the uncertainties are statistical and systematic, respectively. Using these observables together with a recent measurement of the Bs0_{s}^{0} mixing phase −2βs_{s} leads to the first extraction of the CKM angle γ from Bs0_{s}^{0}  → Ds_{s}^{∓} K±^{±} decays, finding γ = (11543+28_{− 43}^{+ 28} )° modulo 180° at 68% CL, where the error contains both statistical and systematic uncertainties.We report on measurements of the time-dependent CP violating observables in Bs0DsK±B^0_s\rightarrow D^{\mp}_s K^{\pm} decays using a dataset corresponding to 1.0 fb1^{-1} of pp collisions recorded with the LHCb detector. We find the CP violating observables Cf=0.53±0.25±0.04C_f=0.53\pm0.25\pm0.04, AfΔΓ=0.37±0.42±0.20A^{\Delta\Gamma}_f=0.37\pm0.42\pm0.20, AfˉΔΓ=0.20±0.41±0.20A^{\Delta\Gamma}_{\bar{f}}=0.20\pm0.41\pm0.20, Sf=1.09±0.33±0.08S_f=-1.09\pm0.33\pm0.08, Sfˉ=0.36±0.34±0.08S_{\bar{f}}=-0.36\pm0.34\pm0.08, where the uncertainties are statistical and systematic, respectively. Using these observables together with a recent measurement of the Bs0B^0_s mixing phase 2βs-2\beta_s leads to the first extraction of the CKM angle γ\gamma from Bs0DsK±B^0_s \rightarrow D^{\mp}_s K^{\pm} decays, finding γ\gamma = (11543+28_{-43}^{+28})^\circ modulo 180^\circ at 68% CL, where the error contains both statistical and systematic uncertainties

    A study of CP violation in B-+/- -&gt; DK +/- and B-+/- -&gt; D pi(+/-) decays with D -&gt; (KSK +/-)-K-0 pi(-/+) final states

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    A first study of CP violation in the decay modes B±[KS0K±π]Dh±B^\pm\to [K^0_{\rm S} K^\pm \pi^\mp]_D h^\pm and B±[KS0Kπ±]Dh±B^\pm\to [K^0_{\rm S} K^\mp \pi^\pm]_D h^\pm, where hh labels a KK or π\pi meson and DD labels a D0D^0 or D0\overline{D}^0 meson, is performed. The analysis uses the LHCb data set collected in pppp collisions, corresponding to an integrated luminosity of 3 fb1^{-1}. The analysis is sensitive to the CP-violating CKM phase γ\gamma through seven observables: one charge asymmetry in each of the four modes and three ratios of the charge-integrated yields. The results are consistent with measurements of γ\gamma using other decay modes

    Measurement of Upsilon production in collisions at root s=2.76 TeV

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    The production of Υ(1S)\Upsilon(1S), Υ(2S)\Upsilon(2S) and Υ(3S)\Upsilon(3S) mesons decaying into the dimuon final state is studied with the LHCb detector using a data sample corresponding to an integrated luminosity of 3.3 pb1pb^{-1} collected in proton-proton collisions at a centre-of-mass energy of s=2.76\sqrt{s}=2.76 TeV. The differential production cross-sections times dimuon branching fractions are measured as functions of the Υ\Upsilon transverse momentum and rapidity, over the ranges $p_{\rm T} Upsilon(1S) X) x B(Upsilon(1S) -> mu+mu-) = 1.111 +/- 0.043 +/- 0.044 nb, sigma(pp -> Upsilon(2S) X) x B(Upsilon(2S) -> mu+mu-) = 0.264 +/- 0.023 +/- 0.011 nb, sigma(pp -> Upsilon(3S) X) x B(Upsilon(3S) -> mu+mu-) = 0.159 +/- 0.020 +/- 0.007 nb, where the first uncertainty is statistical and the second systematic

    Study of forward Z + jet production in pp collisions at √s=7 TeV

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    A measurement of the Z(μ+μ)Z(\rightarrow\mu^+\mu^-)+jet production cross-section in pppp collisions at a centre-of-mass energy s=7\sqrt{s} = 7 TeV is presented. The analysis is based on an integrated luminosity of 1.0fb11.0\,\text{fb}^{-1} recorded by the LHCb experiment. Results are shown with two jet transverse momentum thresholds, 10 and 20 GeV, for both the overall cross-section within the fiducial volume, and for six differential cross-section measurements. The fiducial volume requires that both the jet and the muons from the Z boson decay are produced in the forward direction (2.0<η<4.52.0<\eta<4.5). The results show good agreement with theoretical predictions at the second-order expansion in the coupling of the strong interaction.A measurement of the Z(μ+μ)Z(\rightarrow\mu^+\mu^-)+jet production cross-section in pppp collisions at a centre-of-mass energy s=7\sqrt{s} = 7 TeV is presented. The analysis is based on an integrated luminosity of 1.0fb11.0\,\text{fb}^{-1} recorded by the LHCb experiment. Results are shown with two jet transverse momentum thresholds, 10 and 20 GeV, for both the overall cross-section within the fiducial volume, and for six differential cross-section measurements. The fiducial volume requires that both the jet and the muons from the Z boson decay are produced in the forward direction (2.0<η<4.52.0<\eta<4.5). The results show good agreement with theoretical predictions at the second-order expansion in the coupling of the strong interaction

    Studies of beauty baryon decays to D0ph− and Λ+ch− final states

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    Association of anandamide and 2-arachidonoylglycerol concentrations with clinical features and body mass index in eating disorders and obesity

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    Altres ajuts: This manuscript and research were supported by grants from the Delegación del Gobierno para el Plan Nacional sobre Drogas (2021I031) and cofounded by FEDER funds/European Regional Development Fund (ERDF), a way to build Europe. CIBER Obn, CIBERSAM, and CIBERDEM are initiatives of ISCIII. This study has also been funded by Instituto de Salud Carlos III through the grant CM21/00172 (IB) (Co-funded by European Social Fund. ESF investing in your future). RG is supported by the Catalan Institution for Research and Advanced Studies. (ICREA-Academia, 2021-Programme)Anandamide (AEA) and 2-arachidonoylglycerol (2-AG) play a pivotal role in stimulating motivational behavior toward food and energy metabolism. Aberrant functioning of the endocannabinoid system has been observed in extreme weight conditions (EWCs), suggesting it may influence pathophysiology. Then, we aimed to analyze fasting AEA and 2-AG plasma concentrations among individuals with EWC (i.e., anorexia nervosa [AN] and obesity with and without eating disorders [EDs]) compared with healthy controls (HCs), and its association with clinical variables and body mass index (BMI). The sample included 113 adult women. Fifty-seven belonged to the obesity group, 37 without EDs (OB-ED) and 20 with ED (OB+ED classified within the binge spectrum disorders), 27 individuals from the AN group, and 29 from the HC group. Peripheral blood samples, several clinical variables, and BMI were evaluated. Unlike 2-AG, AEA concentrations showed significant differences between groups (p < 0.001). Increased AEA was observed in the OB-ED and OB+ED compared with both HC and AN group, respectively. Likewise, AEA was differentially associated with emotional dysregulation, general psychopathology, food addiction, and BMI in all clinical groups. These results support the interaction between biological and clinical factors contributing to delineating vulnerability pathways in EWC that could help fit personalized therapeutic approaches

    Creación del recurso didáctico online. Prácticas de redacción periodística: textos informativos

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    Este proyecto consiste en el diseño, elaboración y publicación online del recurso didáctico "Prácticas de redacción periodística: textos informativos", que complementa a las clases prácticas de la asignatura Teoría y práctica del periodismo
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