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Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Resonances and CP violation in B-s(0) and (B)over-bar(s)(0) -> j psi K+K- decays in the mass region above the I center dot(1020) Type Journal Article
Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 037 - 28pp
Keywords B physics; CP violation; Spectroscopy; Hadron-Hadron scattering (experiments)
Abstract The decays of B (s) (0) and mesons into the J/psi K (+) K (-) final state are studied in the K (+) K (-) mass region above the I center dot(1020) meson in order to determine the resonant substructure and measure the CP-violating phase, I center dot (s) , the decay width, I“ (s) , and the width difference between light and heavy mass eigenstates, Delta I” (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 I center dot (s) = 119 +/- 107 +/- 34 mrad. A combination with previous LHCb measurements using similar decays into the J/psi pi (+) pi (-) and J/psi I center dot(1020) final states gives I center dot (s) = 1 +/- 37 mrad, consistent with the Standard Model prediction.
Address (down) [Bediaga, I.; Miranda, J. M. De; Massafferri, A.; Molina Rodriguez, J.; Reis, A. C. dos; Rodrigues, A. B.; Salustino Guimaraes, V.; Soares Lavra, I.; Tourinho Jadallah Aoude, R.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: liming.zhang@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000407690800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3255
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of forward W -> e nu production in pp collisions at root s=8 TeV Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 030 - 29pp
Keywords Electroweak interaction; Hadron-Hadron scattering (experiments); QCD
Abstract A measurement of the cross-section for W -> e nu production in pp collisions is presented using data corresponding to an integrated luminosity of 2 fb(-1) collected by the LHCb experiment at a centre-of-mass energy of root s = 8 TeV. The electrons are required to have more than 20 GeV of transverse momentum and to lie between 2.00 and 4.25 in pseudorapidity. The inclusive W production cross-sections, where the W decays to e nu, are measured to be W-sigma(+)-> e(+)nu(e)= 1124.4 +/- 2.1 +/- 21.5 +/- 11.2 +/- 13.0 pb, W-sigma(-)-> e(-)(nu) over bar (e) = 809.0 +/- 1.9 +/- 18.1 +/- 7.0 +/- 9.4 pb, where the first uncertainties are statistical, the second are systematic, the third are due to the knowledge of the LHC beam energy and the fourth are due to the luminosity determination. Differential cross-sections as a function of the electron pseudorapidity are measured. The W+/W- cross-section ratio and production charge asymmetry are also reported. Results are compared with theoretical predictions at next-to-next-to-leading order in perturbative quantum chromodynamics. Finally, in a precise test of lepton universality, the ratio of W boson branching fractions is determined to be B(W -> e nu)/B(W -> μnu) = 1.020 +/- 0.002 +/- 0.019, where the first uncertainty is statistical and the second is systematic.
Address (down) [Bediaga, I.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil, Email: marek.sirendi@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000386669800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2848
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Evidence for the two-body charmless baryonic decay B+ -> p(Lambda)over-bar Type Journal Article
Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 162 - 18pp
Keywords B physics; Branching fraction; Flavor physics; Hadron-Hadron scattering (experiments)
Abstract A search for the rare two-body charmless baryonic decay B+ -> p (Lambda) over bar is performed with pp collision data, corresponding to an integrated luminosity of 3 fb(-1), collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. An excess of B+ -> p (Lambda) over bar candidates with respect to background expectations is seen with a statistical significance of 4.1 standard deviations, and constitutes the first evidence for this decay. The branching fraction, measured using the B+ -> K-S(0)pi(+) decay for normalisation, is B(B+ -> p (Lambda) over bar) = (2.4(-0.8)(+)(+1.0) +/- 0.3) x 10(-7), where the first uncertainty is statistical and the second systematic.
Address (down) [Bediaga, I.; De Mirandal, J. M.; Gomes, A.; Massafferril, A.; Molina Rodriguezl, J.; dos Reis, A. C.; Rodrigues, A. B.; Salustino Guimaraes, V.; Lavra, I. Soares; Vieira, D.] CBPF, Rio De Janeiro, Brazil, Email: eduardo.rodrigues@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000401067200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3131
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title New algorithms for identifying the flavour of B-0 mesons using pions and protons Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 4 Pages 238 - 15pp
Keywords
Abstract Two new algorithms for use in the analysis of pp collision are developed to identify the flavour of B mesons at production using pions and protons from the hadronization process. The algorithms are optimized and calibrated on data, using B-0 -> D- pi(+) decays from pp collision data collected by LIICh at centre -of -mass energies of 7 and 8 TeV. The tagging power of the new pion algorithm is 60% greater than the previously available one; the algorithm using protons to identify the flavour of a B-0 meson is the first of its kind.
Address (down) [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: marta.calvi@mib.infn.it
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000399448700008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3120
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Observation of B+ -> J/psi 3 pi(+)2 pi(-) and B+ -> psi (2S)pi(+)pi(+)pi(-) decays Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 2 Pages 72 - 12pp
Keywords
Abstract The decays B+-> J/psi 3 pi(+)2 pi(-) and B+ -> psi(2S)pi(+)pi(+)pi(-) 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 8 TeV. The branching fractions relative to that of B+ -> psi(2S)K+ are measured to be B(B+-> J/psi 3 pi(+)2 pi(-))/B(B+ -> psi (2S)K+) = (1.88 +/- 0.17 +/- 0.09)x10(-2). B(B+ -> psi(2S)pi(+)pi(+)pi(-))/B(B+ -> psi (2S)K+) = (3.04 +/- 0.50 +/- 0.26)X10(-2) where the first uncertainties are statistical and the second are systematic.
Address (down) [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil, Email: Ivan.Belyaev@itep.ru
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000394161100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2991
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Observation of the Annihilation Decay Mode B-0 -> K+K- Type Journal Article
Year 2017 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 118 Issue 8 Pages 081801 - 9pp
Keywords
Abstract A search for the B-0 -> K+K- decay is performed using pp-collision data collected by LHCb. The data set corresponds to integrated luminosities of 1.0 and 2.0 fb(-1) at center-of-mass energies of 7 and 8 TeV, respectively. This decay is observed for the first time, with a significance of more than 5 standard deviations. The analysis also results in an improved measurement of the branching fraction for the B-s(0) -> pi(+)pi(-) decay. The measured branching fractions are B(B-0 -> K+K-) = (7.80 +/- 1.27 +/- 0.81 +/- 0.21) x 10(-8) and B(B-s(0) -> pi(+)p(-)) = (6.91 +/- 0.54 +/- 0.63 +/- 0.19 +/- 0.40) x 10(-7). The first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the B-0 -> K+pi(-) branching fraction used as a normalization. For the B-s(0) mode, the fourth accounts for the uncertainty on the ratio of the probabilities for b quarks to hadronize into B-s(0) and B-0 mesons.
Address (down) [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000394667300004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2965
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of the b- Quark Production Cross Section in 7 and 13 TeV pp Collisions Type Journal Article
Year 2017 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 118 Issue 5 Pages 052002 - 11pp
Keywords
Abstract Measurements of the cross section for producing b quarks in the reaction pp -> b (b) over barX are reported in 7 and 13 TeV collisions at the LHC as a function of the pseudorapidity. in the range 2 < eta < 5 covered by the acceptance of the LHCb experiment. The measurements are done using semileptonic decays of b-flavored hadrons decaying into a ground-state charmed hadron in association with a muon. The cross sections in the covered. range are 72.0 +/- 0.3 +/- 6.8 and 154.3 +/- 1.5 +/- 14.3 +/- μb for 7 and 13 TeV. The ratio is 2.14 +/- 0.02 +/- 0.13, where the quoted uncertainties are statistical and systematic, respectively. The agreement with theoretical expectation is good at 7 TeV, but differs somewhat at 13 TeV. The measured ratio of cross sections is larger at lower eta than the model prediction.
Address (down) [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Kucewicz, W.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000396415600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2970
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurements of charm mixing and CP violation using D-0 -> K-+/-pi(-/+) decays Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 95 Issue 5 Pages 052004 - 14pp
Keywords
Abstract Measurements of charm mixing and CP violation parameters from the decay-time-dependent ratio of D-0 -> K+pi(-) to D-0 -> K-pi(+) decay rates and the charge-conjugate ratio are reported. The analysis uses (B) over bar -> D*(+) μX-, and charge-conjugate decays, where D *(+) -> D-0 pi(+), and D-0 -> K-+/-pi(-/+). The pp collision data are recorded by the LHCb experiment at center-of-mass energies root s = 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb(-1). The data are analyzed under three hypotheses: (i) mixing assuming CP symmetry, (ii) mixing assuming no direct CP violation in the Cabibbo-favored or doubly Cabibbo-suppressed decay amplitudes, and (iii) mixing allowing either direct CP violation and/or CP violation in the superpositions of flavor eigenstates defining the mass eigenstates. The data are also combined with those from a previous LHCb study of D-0 -> K pi decays from a disjoint set of D*(+) candidates produced directly in pp collisions. In all cases, the data are consistent with the hypothesis of CP symmetry.
Address (down) [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Kucewicz, W.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000399254800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3056
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Search for the CP-violating strong decays eta -> pi(+)pi(-) and eta ' (958) -> pi(+)pi(-) Type Journal Article
Year 2017 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 764 Issue Pages 233-240
Keywords
Abstract A search for the CP-violating strong decays eta -> pi(+)pi(-) and eta ' (958) -> pi(+)pi(-) has been performed using approximately 2.5 x 10(7) events of each of the decays D+ -> pi(+)pi(+)pi(-) and D-s(+) -> pi(+)pi(+)pi(-), recorded by the LHCb experiment. The data set corresponds to an integrated luminosity of 3.0 fb(-1) of pp collision data recorded during LHC Run 1 and 0.3fb(-1) recorded in Run 2. No evidence is seen for D-(s)(+) -> pi(+)eta((')) with eta((')) -> pi(+)pi(-), and upper limits at 90% confidence level are set on the branching fractions, B(eta -> pi(+)pi(-)) < 1.6 x 10(-5) and B(eta' -> pi(+)pi(-)) < 1.8 x 10(-5). The limit for the eta decay is comparable with the existing one, while that for the eta' is a factor of three smaller than the previous limit.
Address (down) [Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000390127100035 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2993
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of CP asymmetries in D-+/- -> eta 'pi(+/-) and D-S(+/-) -> eta 'pi(+/-) decays Type Journal Article
Year 2017 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 771 Issue Pages 21-30
Keywords
Abstract A search for CP violation in D-+/- -> eta 'pi(+/-) and D-S(+/-) -> eta 'pi(+/-) decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 3 fb(-1), recorded by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The measured CP-violating charge asymmetries are A(CP)(D-+/- -> eta 'pi(+/-)) = (-0.61 +/- 0.72 +/- 0.53 +/- 0.12)% and A(CP)(D-S(+/-) -> eta 'pi(+/-)) = (-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 A(CP)(D-+/- -> K-S(0)pi(+/-)) and A(CP)(D-S(+/-) -> phi pi(+/-)) measurements used for calibration. The results represent the most precise measurements of these asymmetries to date.
Address (down) [Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000406183300005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3259
Permanent link to this record