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Author (down) LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of the track reconstruction efficiency at LHCb Type Journal Article
Year 2015 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 10 Issue Pages P02007 - 23pp
Keywords Large detector-systems performance; Pattern recognitio, cluster finding, calibration and fitting methods; Performance of High Energy Physics Detectors
Abstract The determination of track reconstruction efficiencies at LHCb using J/psi -> mu(+)mu(-) decays is presented. Efficiencies above 95% are found for the data taking periods in 2010, 2011, and 2012. The ratio of the track reconstruction efficiency of muons in data and simulation is compatible with unity and measured with an uncertainty of 0.8% for data taking in 2010, and at a precision of 0.4% for data taking in 2011 and 2012. For hadrons an additional 1.4% uncertainty due to material interactions is assumed. This result is crucial for accurate cross section and branching fraction measurements in LHCb.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: michel.de.cian@cern.ch
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000351664800054 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2171
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Author (down) LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of B-c(+) Production in Proton-Proton Collisions at root s=8 TeV Type Journal Article
Year 2015 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 114 Issue 13 Pages 132001 - 9pp
Keywords
Abstract Production of B-c(+) mesons in proton-proton collisions at a center-of-mass energy of 8 TeV is studied with data corresponding to an integrated luminosity of 2.0 fb(-1) recorded by the LHCb experiment. The ratio of production cross sections times branching fractions between the B_c. J/psi pi(+) and B+ -> J/psi K+ decays is measured as a function of transverse momentum and rapidity in the regions 0 < p(T) < 20 GeV/c and 2.0 < y < 4.5. The ratio in this kinematic range is measured to be (0.683 +/- 0.018 +/- 0.009)%, where the first uncertainty is statistical and the second systematic.
Address [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, 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:000352192600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2182
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Author (down) LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of indirect CP asymmetries in D-0 -> K-K+ and D-0 -> pi(-)pi(+) decays using semileptonic B decays Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 043 - 19pp
Keywords CP violation; Charm physics; Lifetime; Hadron-Hadron Scattering
Abstract Time-dependent CP asymmetries in the decay rates of the singly Cabibbo-suppressed decays D-0 -> K-K+ and D-0 -> pi (-) pi(+) are measured in pp collision data corresponding to an integrated luminosity of 3.0 fb(-1) collected by the LHCb experiment. The D-0 mesons are produced in semileptonic b-hadron decays, where the charge of the accompanying muon is used to determine the initial state as D-0 or (D) over bar (0). The asymmetries in effective lifetimes between D-0 and (D) over bar (0) decays, which are sensitive to indirect CP violation, are determined to be A(Gamma) (K-K+) = (-0.134 +/- 0.077(-0.034)(+0.026))%, A(Gamma) (pi(-)pi(+)) = -0.092 +/- 0.145(-0.033)(+0.025))%, where the first uncertainties are statistical and the second systematic. This result is in agreement with previous measurements and with the hypothesis of no indirect CP violation in D (0) decays.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] CBPF, Rio De Janeiro, Brazil, Email: Jeroen.van.Tilburg@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:000353555500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2197
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Author (down) LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Study of the rare B-s(0) and B-0 decays into the pi(+) pi(-) mu(+) mu(-) final state Type Journal Article
Year 2015 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 743 Issue Pages 46-55
Keywords
Abstract A search for the rare decays B-s(0) -> pi(+) pi-mu(+) mu-and B-0 -> pi(+) pi-mu(+) mu-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 0.5-1.3GeV/c(2) and with muon pairs that do not originate from a resonance are considered. The first observation of the decay B-s(0) -> pi(+) pi-mu(+) mu- and the first evidence of the decay B-0 -> pi(+) pi-mu(+) mu-are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(B-s(0) -> pi(+) pi-mu(+) mu(-)) =(8.6 +/- 1.5(stat) +/- 0.7(syst) +/- 0.7 (norm)) x 10(-8) and B(B-0 -> pi(+) pi-mu(+) mu(-)) =(2.11 +/- 0.51(stat) +/- 0.15(syst) +/- 0.16(norm)) x10(-8), where the third uncertainty is due to the branching fraction of the decay B-0. -> J/Psi(mu(+) mu(-)) K*(892)(0)(-> K+ pi(-)), used as a normalisation.
Address [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodrigues, B. Osorio; dos Reis, A. C.; Rodrigues, A. B.] CBPF, Rio De Janeiro, Brazil, Email: mirco.dorigo@cern.ch
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:000352147500006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2199
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Author (down) LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title 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 Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 024 - 27pp
Keywords Spectroscopy; Hadron-Hadron Scattering; QCD; B physics; Flavor physics
Abstract Invariant mass distributions of B (+) pi (-) and B (0) pi (+) 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 B (0) pi (+) 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.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Rodrigues, B. Osorio; dos Reis, A. C.; Rodrigues, A. B.] CBPF, Rio De Janeiro, Brazil, Email: vladimir.gligorov@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:000353555200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2217
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