136 research outputs found

    Mesure de la polarisation du baryon lourd Λb avec le dĂ©tecteur LHCb. Recherche de la violation directe de la symĂ©trie de renversement du temps T

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    This thesis subject focuses on the study of the weak decay of the beauty baryon Λb →Λ J/Κ with the LHCb detector. Firstly, it offers the opportunity to test the validity of the CP symmetry in the baryon sector and, secondly, the one of time-reversal symmetry T whose experimental evidence is tiny. Emphasis is put on the measurement of the components of the polarization-vectors of the Λb and the ones of the intermediate resonances Λ and J/Κ, whose some components exhibit a clear sign of direct T violation. The development of a phenomenological model of the Λb → Λ J/Κ decay in the framework of the helicity formalism of Jacob-Wick and Jackson leads to the calculations of the angular distributions which allow to deduce the values of the polarization vector components. A thorough study of the reconstruction and the selection of the data recorded by LHCb in 2011 and 2012 is exposed, as well as a full Monte Carlo simulation. The compatibility between the measured values of the polarization-vector of Λb and Λ ̄b implies the absence of CP violation. The direct violation of the T symmetry has not been observed in the hadronic decays of Λb ( Λ ̄b). On another side, first measurements of the longitudinal polarization of Λb and of Λ ̄b well as the longitudinal polarization of the vector-meson J/Κ have been performed in the context of this work.Le sujet de cette thĂšse porte sur l’étude de la dĂ©sintĂ©gration faible du baryon beau Λb → Λ J/Κ avec le dĂ©tecteur LHCb. Cette Ă©tude offre la possibilitĂ© de tester, d’une part, la validitĂ© de la symĂ©trie CP dans le secteur baryonique et, d’autre part, celle de la symĂ©trie de renversement du temps T dont les preuves expĂ©rimentales de sa violation sont limitĂ©es. L’accent est mis sur la mesure des composantes des vecteurs-polarisations du Λb et des rĂ©sonances intermĂ©diaires Λ et J/Κ, dont certaines du type ”T-odd” (impaires par T) reprĂ©sentent un signe clair de violation directe de T. Le dĂ©veloppement d’un modĂšle phĂ©nomĂ©nologique des dĂ©sintĂ©grations Λb → Λ J/Κ dans le cadre du formalisme d’hĂ©licitĂ© de Jacob-Wick et de Jackson conduit aux calculs de distributions angulaires qui permettent de dĂ©duire les valeurs des composantes des vecteurs-polarisations. Une Ă©tude approfondie de la reconstruction et de la sĂ©lection des donnĂ©es enregistrĂ©es par LHCb en 2011 et 2012 est exposĂ©e, ainsi qu’une simulation Monte-Carlo complĂšte. La compatibilitĂ© entre les valeurs mesurĂ©es des vecteurs-polarisation du Λb et du Λ ̄b implique l’absence de violation de CP. La violation directe de la symĂ©trie T n’a pas non plus Ă©tĂ© observĂ©e dans les dĂ©sintĂ©grations hadroniques du Λb (Λ ̄b). Sur un autre plan, les premiĂšres mesures des polarisations longitudinales du Λb et du Λ ̄b ainsi que de la polarisation longitudinale du mĂ©son-vecteur J/Κ ont Ă©tĂ© rĂ©alisĂ©es dans le cadre de ce travail

    Chromosomal aberrations in benign and malignant Bilharzia-associated bladder lesions analyzed by comparative genomic hybridization

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    BACKGROUND: Bilharzia-associated bladder cancer (BAC) is a major health problem in countries where urinary schistosomiasis is endemic. Characterization of the genetic alterations in this cancer might enhance our understanding of the pathogenic mechanisms of the disease but, in contrast to nonbilharzia bladder cancer, BAC has rarely been the object of such scrutiny. In the present study, we aimed to characterize chromosomal imbalances in benign and malignant post-bilharzial lesions, and to determine whether their unique etiology yields a distinct cytogenetic profile as compared to chemically induced bladder tumors. METHODS: DNAs from 20 archival paraffin-embedded post-bilharzial bladder lesions (6 benign and 14 malignant) obtained from Sudanese patients (12 males and 8 females) with a history of urinary bilharziasis were investigated for chromosomal imbalances using comparative genomic hybridization (CGH). Subsequent FISH analysis with pericentromeric probes was performed on paraffin sections of the same cases to confirm the CGH results. RESULTS: Seven of the 20 lesions (6 carcinomas and one granuloma) showed chromosomal imbalances varying from 1 to 6 changes. The most common chromosomal imbalances detected were losses of 1p21-31, 8p21-pter, and 9p and gain of 19p material, seen in three cases each, including the benign lesion. CONCLUSION: Most of the detected imbalances have been repeatedly reported in non-bilharzial bladder carcinomas, suggesting that the cytogenetic profiles of chemical- and bilharzia-induced carcinomas are largely similar. However, loss of 9p seems to be more ubiquitous in BAC than in bladder cancer in industrialized countries

    The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

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    Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

    Observation of the B0 → ρ0ρ0 decay from an amplitude analysis of B0 → (π+π−)(π+π−) decays

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    Proton–proton collision data recorded in 2011 and 2012 by the LHCb experiment, corresponding to an integrated luminosity of 3.0 fb−1 , are analysed to search for the charmless B0→ρ0ρ0 decay. More than 600 B0→(π+π−)(π+π−) signal decays are selected and used to perform an amplitude analysis, under the assumption of no CP violation in the decay, from which the B0→ρ0ρ0 decay is observed for the first time with 7.1 standard deviations significance. The fraction of B0→ρ0ρ0 decays yielding a longitudinally polarised final state is measured to be fL=0.745−0.058+0.048(stat)±0.034(syst) . The B0→ρ0ρ0 branching fraction, using the B0→ϕK⁎(892)0 decay as reference, is also reported as B(B0→ρ0ρ0)=(0.94±0.17(stat)±0.09(syst)±0.06(BF))×10−6

    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 fb−1^{-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 fb−1^{-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(b→ηcX)=(4.88±0.64±0.25±0.67B)×10−3B ( 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 pp‟p\overline{p} final state with the LHCb detector, in the rapidity range 2.06.5 GeV/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 fb−1^{-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 fb−1^{-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 pp‟p\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(b→ηcX)=(4.88 ± 0.64 ± 0.29 ± 0.67B)×10−3{\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±0.1 MeV ⁣/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 fb−1^{-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 fb−1^{-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(b→ηcX)=(4.88±0.64±0.29±0.67B)×10−3B ( 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

    Angular analysis of the B-0 -> K*(0) e(+) e(-) decay in the low-q(2) region

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    An angular analysis of the B0→K∗0e+e−B^0 \rightarrow K^{*0} e^+ e^- decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 {\mbox{fb}^{-1}}, collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared (q2q^2) interval between 0.002 and 1.120 GeV2 ⁣/c4{\mathrm{\,Ge\kern -0.1em V^2\!/}c^4}. The angular observables FLF_{\mathrm{L}} and ATReA_{\mathrm{T}}^{\mathrm{Re}} which are related to the K∗0K^{*0} polarisation and to the lepton forward-backward asymmetry, are measured to be FL=0.16±0.06±0.03F_{\mathrm{L}}= 0.16 \pm 0.06 \pm0.03 and ATRe=0.10±0.18±0.05A_{\mathrm{T}}^{\mathrm{Re}} = 0.10 \pm 0.18 \pm 0.05, where the first uncertainty is statistical and the second systematic. The angular observables AT(2)A_{\mathrm{T}}^{(2)} and ATImA_{\mathrm{T}}^{\mathrm{Im}} which are sensitive to the photon polarisation in this q2q^2 range, are found to be AT(2)=−0.23±0.23±0.05A_{\mathrm{T}}^{(2)} = -0.23 \pm 0.23 \pm 0.05 and ATIm=0.14±0.22±0.05A_{\mathrm{T}}^{\mathrm{Im}} =0.14 \pm 0.22 \pm 0.05. The results are consistent with Standard Model predictions.An angular analysis of the B0^{0} → K^{*}^{0} e+^{+} e−^{−} decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 fb−1^{−1}, collected by the LHCb experiment in pp collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared (q2^{2}) interval between 0.002 and 1.120 GeV2^{2} /c4^{4}. The angular observables FL_{L} and ATRe_{T}^{Re} which are related to the K^{*}^{0} polarisation and to the lepton forward-backward asymmetry, are measured to be FL_{L} = 0.16 ± 0.06 ± 0.03 and ATRe_{T}^{Re}  = 0.10 ± 0.18 ± 0.05, where the first uncertainty is statistical and the second systematic. The angular observables AT(2)_{T}^{(2)} and ATIm_{T}^{Im} which are sensitive to the photon polarisation in this q2^{2} range, are found to be AT(2)_{T}^{(2)}  = − 0.23 ± 0.23 ± 0.05 and ATIm_{T}^{Im}  = 0.14 ± 0.22 ± 0.05. The results are consistent with Standard Model predictions.An angular analysis of the B0→K∗0e+e−B^0 \rightarrow K^{*0} e^+ e^- decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 {\mbox{fb}^{-1}}, collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared (q2q^2) interval between 0.002 and 1.120 GeV2 ⁣/c4{\mathrm{\,Ge\kern -0.1em V^2\!/}c^4}. The angular observables FLF_{\mathrm{L}} and ATReA_{\mathrm{T}}^{\mathrm{Re}} which are related to the K∗0K^{*0} polarisation and to the lepton forward-backward asymmetry, are measured to be FL=0.16±0.06±0.03F_{\mathrm{L}}= 0.16 \pm 0.06 \pm0.03 and ATRe=0.10±0.18±0.05A_{\mathrm{T}}^{\mathrm{Re}} = 0.10 \pm 0.18 \pm 0.05, where the first uncertainty is statistical and the second systematic. The angular observables AT(2)A_{\mathrm{T}}^{(2)} and ATImA_{\mathrm{T}}^{\mathrm{Im}} which are sensitive to the photon polarisation in this q2q^2 range, are found to be AT(2)=−0.23±0.23±0.05A_{\mathrm{T}}^{(2)} = -0.23 \pm 0.23 \pm 0.05 and ATIm=0.14±0.22±0.05A_{\mathrm{T}}^{\mathrm{Im}} =0.14 \pm 0.22 \pm 0.05. The results are consistent with Standard Model predictions

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

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    A study of CP violation in B-+/- -> DK +/- and B-+/- -> D pi(+/-) decays with D -> (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±→[KS0K∓π±]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 D‟0\overline{D}^0 meson, is performed. The analysis uses the LHCb data set collected in pppp collisions, corresponding to an integrated luminosity of 3 fb−1^{-1}. The analysis is sensitive to the CP-violating CKM phase Îł\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 Îł\gamma using other decay modes

    Study of the rare B-s(0) and B-0 decays into the pi(+) pi(-) mu(+) mu(-) final state

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    A search for the rare decays Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1^{-1} collected by the LHCb detector in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV. Decay candidates with pion pairs that have invariant mass in the range 0.5-1.3 GeV/c2c^2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and the first evidence of the decay B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- are obtained and the branching fractions are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7 (norm))×10−8\mathcal{B}(B_s^0 \to \pi^+\pi^-\mu^+\mu^-)=(8.6\pm 1.5\,({\rm stat}) \pm 0.7\,({\rm syst})\pm 0.7\,({\rm norm}))\times 10^{-8} and B(B0→π+π−Ό+Ό−)=(2.11±0.51 (stat)±0.15 (syst)±0.16 (norm))×10−8\mathcal{B}(B^0 \to \pi^+\pi^-\mu^+\mu^-)=(2.11\pm 0.51\,({\rm stat}) \pm 0.15\,({\rm syst})\pm 0.16\,({\rm norm}) )\times 10^{-8}, where the third uncertainty is due to the branching fraction of the decay B0→J/ψ(→Ό+Ό−)K∗(890)0(→K+π−)B^0\to J/\psi(\to \mu^+\mu^-)K^*(890)^0(\to K^+\pi^-), used as a normalisation.A search for the rare decays Bs0→π+π−Ό+Ό− and B0→π+π−Ό+Ό− is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1 collected by the LHCb detector in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV . Decay candidates with pion pairs that have invariant mass in the range 0.5–1.3 GeV/c2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0→π+π−Ό+Ό− and the first evidence of the decay B0→π+π−Ό+Ό− are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))×10−8 and B(B0→π+π−Ό+Ό−)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))×10−8 , where the third uncertainty is due to the branching fraction of the decay B0→J/ψ(→Ό+Ό−)K⁎(892)0(→K+π−) , used as a normalisation.A search for the rare decays Bs0→π+π−Ό+Ό− and B0→π+π−Ό+Ό− is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1 collected by the LHCb detector in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV . Decay candidates with pion pairs that have invariant mass in the range 0.5–1.3 GeV/c2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0→π+π−Ό+Ό− and the first evidence of the decay B0→π+π−Ό+Ό− are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))×10−8 and B(B0→π+π−Ό+Ό−)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))×10−8 , where the third uncertainty is due to the branching fraction of the decay B0→J/ψ(→Ό+Ό−)K⁎(892)0(→K+π−) , used as a normalisation.A search for the rare decays Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1^{-1} collected by the LHCb detector in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV. Decay candidates with pion pairs that have invariant mass in the range 0.5-1.3 GeV/c2c^2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0→π+π−Ό+Ό−B_s^0 \to \pi^+\pi^-\mu^+\mu^- and the first evidence of the decay B0→π+π−Ό+Ό−B^0 \to \pi^+\pi^-\mu^+\mu^- are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−Ό+Ό−)=(8.6±1.5 (stat)±0.7 (syst)±0.7 (norm))×10−8\mathcal{B}(B_s^0 \to \pi^+\pi^-\mu^+\mu^-)=(8.6\pm 1.5\,({\rm stat}) \pm 0.7\,({\rm syst})\pm 0.7\,({\rm norm}))\times 10^{-8} and B(B0→π+π−Ό+Ό−)=(2.11±0.51 (stat)±0.15 (syst)±0.16 (norm))×10−8\mathcal{B}(B^0 \to \pi^+\pi^-\mu^+\mu^-)=(2.11\pm 0.51\,({\rm stat}) \pm 0.15\,({\rm syst})\pm 0.16\,({\rm norm}) )\times 10^{-8}, where the third uncertainty is due to the branching fraction of the decay B0→J/ψ(→Ό+Ό−)K∗(890)0(→K+π−)B^0\to J/\psi(\to \mu^+\mu^-)K^*(890)^0(\to K^+\pi^-), used as a normalisation

    Precise measurements of the properties of the B-1(5721)(0,+) and B-2*(5747)(0,+) states and observation of B-+,B-0 pi(-,+) mass structures

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    Invariant mass distributions of B+π−B^+\pi^- and B0π+B^0\pi^+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0fb−13.0 fb^{-1} of pppp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B1(5721)0,+B_1(5721)^{0,+} and B2∗(5747)0,+B_2^*(5747)^{0,+} states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 58505850-60006000 MeV in both B+π−B^+\pi^- and B0π+B^0\pi^+ combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ(5840)0,+B_J(5840)^{0,+} and BJ(5960)0,+B_J(5960)^{0,+}, whose masses and widths are obtained under different hypotheses for their quantum numbers.Invariant mass distributions of B+^{+} π−^{−} and B0^{0} π+^{+} combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb−1^{−1} of pp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B1_{1}(5721)0,+^{0,+} and B2^{2}(5747)0,+^{0,+} states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 5850-6000 MeV in both B+^{+} π−^{−} and B0^{0} π+^{+} combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ_{J} (5840)0,+^{0,+} and BJ_{J} (5960)0,+^{0,+}, whose masses and widths are obtained under different hypotheses for their quantum numbers.Invariant mass distributions of B+pi- and B0pi+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb-1 of pp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B_1(5721)^(0,+) and B_2*(5747)^(0,+) states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 5850--6000 MeV in both B+pi- and B0pi+ combinations. The structures are consistent with the presence of four excited B mesons, labelled B_J(5840)^(0,+) and B_J(5960)^(0,+), whose masses and widths are obtained under different hypotheses for their quantum numbers
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