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Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Determination of the branching fractions of B-s(0) -> D-s(-/+) K-/+ and B-0 -> Ds-K+ Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 019 - 16pp
Keywords Hadron-Hadron Scattering; Branching fraction; B physics; Flavor physics
Abstract Measurements are presented of the branching fractions of the decays B-s(0) -> D-s(-/+) K--/+ and B-0 -> Ds-K+ relative to the decays B-s(0) -> D-s(-)pi(+) and B-0 -> D-s(-)pi(+), respectively. The data used correspond to an integrated luminosity of 3.0 fb(-1) of proton-proton collisions. The ratios of branching fractions are B(B-s(0) -> D-s(-/+) K--/+)/B(B-s(0) -> D-s(-)pi(+)) = 0.0752 +/- 0.0015 +/- 0.0019 and B(B-0 -> Ds-K+)/B(B-0 -> D-pi(+)) = 0.0129 +/- 0.0005 +/- 0.0008, where the uncertainties are statistical and systematic, respectively.
Address [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodrigues, B. Osorio; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher (down) 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:000354392500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2230
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Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of forward Z -> e(+)e(-) production at root s=8 TeV Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 109 - 21pp
Keywords Electroweak interaction; QCD; Forward physics; Hadron-Hadron Scattering; proton-proton scattering
Abstract A measurement of the cross-section for Z-boson production in the forward region of pp collisions at 8 TeV centre-of-mass energy is presented. The measurement is based on a sample of Z -> e(+)e(-) decays reconstructed using the LHCb detector, corresponding to an integrated luminosity of 2.0 fb(-1). The acceptance is defined by the requirements 2.0 < eta < 4.5 and p(T) > 20 GeV for the pseudorapidities and transverse momenta of the leptons. Their invariant mass is required to lie in the range 60-120 GeV. The cross-section is determined to be sigma(pp -> Z -> e(+)e(-)) = 93.81 +/- 0.41(stat) +/- 1.48(syst) +/- 1.14(lumi) pb, where the first uncertainty is statistical and the second reflects all systematic effects apart from that arising from the luminosity, which is given as the third uncertainty. Differential cross-sections are presented as functions of the Z-boson rapidity and of the angular variable phi*, which is related to the Z-boson transverse momentum.
Address CBPF, Rio De Janeiro, Brazil, Email: drw1@cam.ac.uk
Corporate Author Thesis
Publisher (down) 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:000354977800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2236
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Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of the forward W boson cross-section in pp collisions at root s = 7 TeV Type Journal Article
Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 12 Issue 12 Pages 079 - 25pp
Keywords Hadron-Hadron Scattering; QCD; Forward physics
Abstract A measurement of the inclusive W -> μnu production cross-section using data from pp collisions at a centre-of-mass energy of root s=7 TeV is presented. The analysis is based on an integrated luminosity of about 1.0 fb(-1) recorded with the LHCb detector. Results are reported for muons with a transverse momentum greater than 20 GeV/c and pseudorapidity between 2.0 and 4.5. The W+ and W- production cross-sections are measured to be sigma(W+->mu+nu)=861.0 +/- 2.0 +/- 11.2 +/- 14.7pb, sigma(W-->mu-(nu)over bar)=675.8 +/- 1.9 +/- 8.8 +/- 11.6pb, where the first uncertainty is statistical, the second is systematic and the third is due to the luminosity determination. Cross-section ratios and differential distributions as functions of the muon pseudorapidity are also presented. The ratio of W+ to W- cross-sections in the same fiducial kinematic region is determined to be sigma(W+->mu+nu)/sigma(W-->mu-(nu)over bar) = 1.274 +/- 0.005 +/- 0.009, where the uncertainties are statistical and systematic, respectively. Results are in good agreement with theoretical predictions at next-to-next-to-leading order in perturbative quantum chromodynamics.
Address Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: simone.bifani@cern.ch
Corporate Author Thesis
Publisher (down) 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:000346250100002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2246
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Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Search for long-lived particles decaying to jet pairs Type Journal Article
Year 2015 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 75 Issue 4 Pages 152 - 12pp
Keywords
Abstract A search is presented for long-lived particles with a mass between 25 and 50 GeV/c(2) and a lifetime between 1 and 200 ps in a sample of proton-proton collisions at a centre-of-mass energy of root s = 7 TeV, corresponding to an integrated luminosity of 0.62 fb(-1), collected by the LHCb detector. The particles are assumed to be pair-produced by the decay of a standard model-like Higgs boson. The experimental signature of the long-lived particle is a displaced vertex with two associated jets. No excess above the background is observed and limits are set on the production cross-section as a function of the long-lived particle mass and lifetime.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Furfaro, E.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.; Santovetti, E.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher (down) 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:000355670500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2260
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of the time-dependent CP asymmetries in B-s(0) -> J/psi K-S(0) Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 131 - 22pp
Keywords CP violation; Hadron-Hadron Scattering; Branching fraction; B physics; Flavor physics
Abstract The first measurement of decay-time-dependent CP asymmetries in the decay B-S(0) -> J/psi K-S(0) and an updated measurement of the ratio of branching fractions B(B-S(0) -> J/psi K-S(0))/B(B-0 -> J/psi K-S(0)) are presented. The results are obtained using data corresponding to an integrated luminosity of 3.0 fb(-1) of proton-proton collisions recorded with the LHCb detector at centre-of-mass energies of 7 and 8 TeV. The results on the CP asymmetries are A(Delta Gamma)(B-S(0) -> J/psi K-S(0)) = 0.49 +/- (0.77)(0.65)(stat) +/- 0.06(syst), C-dir(B-S(0) -> J/psi K-S(0)) = -0.28 +/- 0.41(stat) +/- 0.08(syst), S-mix(B-S(0) -> J/psi K-S(0)) = -0.08 +/- 0.40(stat) +/- 0.08(syst). The ratio B(B-S(0) -> J/psi K-S(0))/B(B-0 -> J/psi K-S(0)) is measured to be 0.0431 +/- 0.0017(stat) +/- 0.0012(syst) +/- 0.0025(f(s)/f(d)), where the last uncertainty is due to the knowledge of the B-S(0) and B-0 production fractions.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: debkr@nikhef.nl
Corporate Author Thesis
Publisher (down) 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:000356954700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2287
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Differential branching fraction and angular analysis of Lambda(0)(b) -> Lambda mu(+)mu(-) decays Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 115 - 29pp
Keywords Rare decay; Hadron-Hadron Scattering; Branching fraction; B physics; Flavour Changing Neutral Currents
Abstract The differential branching fraction of the rare decay Lambda(0)(b) -> Lambda mu(+)mu(-) is measured as a function of q(2), the square of the dimuon invariant mass. The analysis is performed using proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment. Evidence of signal is observed in the q(2) region below the square of the J/psi mass. Integrating over 15 < q(2) < 20 GeV2/c(4) the differential branching fraction is measured as dB(Lambda(0)(b) -> Lambda mu(+)mu(-))/dq(2) = (1.18(-0.08)(+0.09) +/- 0.03 +/- 0.27) x 10(-7) (GeV2/c(4))(-1) where the uncertainties are statistical, systematic and due to the normalisation mode Lambda(0)(b) -> J/psi Lambda , respectively. In the q(2) intervals where the signal is observed, angular distributions are studied and the forward-backward asymmetries in the dimuon (A(FB)(l)) and hadron (A(FB)(h)) systems are measured for the first time. In the range 15 < q(2) < 20GeV(2)/c(4) they are found to be A(FB)(l) = -0.05 +/- 0.09 (stat) +/- 0.03 (syst) and A(FB)(h) = -0.29 +/- 0.07 (stat) +/- 0.03 (syst).
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fisicas CBPF, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher (down) 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:000356955000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2288
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Angular analysis of the B-0 -> K*(0) e(+) e(-) decay in the low-q(2) region Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 064 - 23pp
Keywords Rare decay; Polarization; B physics; Flavour Changing Neutral Currents; Hadron-Hadron Scattering
Abstract An angular analysis of the B-0 -> K(*0)e(+) e(-) decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 fb(-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 (q(2)) interval between 0.002 and 1.120 GeV2/c(4). The angular observables F-L and A(T)(Re) which are related to the K-*0 polarisation and to the lepton forward-backward asymmetry, are measured to be F-L = 0.16 +/- 0.06 +/- 0.03 and A(T)(Re) = 0.10 +/- 0.18 +/- 0.05, where the first uncertainty is statistical and the second systematic. The angular observables A(T)((2)) and A(T)(Im) which are sensitive to the photon polarisation in this q(2) range, are found to be A(T)((2)) = – 0.23 +/- 0.23 +/- 0.05 and A(T)(Im) = 0.14 +/- 0.22 +/- 0.05. The results are consistent with Standard Model predictions.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: schunem@lal.in2p3.fr
Corporate Author Thesis
Publisher (down) 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:000356853700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2292
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of the (eta c)(1S) production cross-section in proton-proton collisions via the decay (eta c)(1S) -> p(p)over-bar Type Journal Article
Year 2015 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 75 Issue 7 Pages 311 - 12pp
Keywords
Abstract The production of the eta(c)(1S) state in protonproton collisions is probed via its decay to the p (p) over bar final state with the LHCb detector, in the rapidity range 2.0 < y < 4.5 and in the meson transverse-momentum range p(T) > 6.5GeV/c. The cross-section for prompt production of eta(c)(1S) mesons relative to the prompt J/psi cross-section is measured, for the first time, to be s sigma(eta c(1S))/sigma J/psi = 1.74 +/- 0.29 +/- 0.28 +/- 0.18(B) at a centre-of-mass energy root s = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb(-1), and s sigma(eta c(1S))/sigma(J/psi) = 1.60 +/- 0.29 +/- 0.25 +/- 0.17(B) at root s = 8 TeV using 2.0 fb(-1). The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the (eta c)(1S) and J/psi decays to the p (p) over bar final state. In addition, the inclusive branching fraction of b-hadron decays into (eta c)(1S) mesons is measured, for the first time, to be B(b -> X-eta c) = (4.88 +/- 0.64 +/- 0.29 +/- 0.67(B)) x10(-3), where the third uncertainty includes also the uncertainty on the J/psi inclusive branching fraction from b-hadron decays. The difference between the J/psi and (eta c)(1S) meson masses is determined to be 114.7 +/- 1.5 +/- 0.1MeV/c(2).
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Furfaro, E.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Santovetti, E.] CBPF, Rio De Janeiro, Brazil, Email: sergey.barsuk@cern.ch
Corporate Author Thesis
Publisher (down) 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:000357479400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2298
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Measurement of CP asymmetries and polarisation fractions in B-s(0) -> K*(0)(K)over-bar*(0) decays Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 166 - 28pp
Keywords CP violation; Hadron-Hadron Scattering; Polarization; B physics; Flavour Changing Neutral Currents
Abstract An angular analysis of the decay B-s(0) -> K*(0)(K) over bar*(0) is performed using pp collisions corresponding to an integrated luminosity of 1.0 fb(-1) collected by the LHCb experiment at a centre-of-mass energy root s = 7TeV. A combined angular and mass analysis separates six helicity amplitudes and allows the measurement of the longitudinal polarisation fraction f(L) = 0.201 +/- 0.057 (stat.) +/- 0.040 (syst.) for the B-s(0) -> K*(892)(0)(K) over bar*(892)(0) decay. A large scalar contribution from the K*(0) (1430) and K*(0) (800) resonances is found, allowing the determination of additional CP asymmetries. Triple product and direct CP asymmetries are determined to be compatible with the Standard Model expectations. The branching fraction B(B-s(0) -> K*(892)(0)(K) over bar*(892)(0)) is measured to be (10.8 +/- 2.1 (stat.) +/- 1.4 (syst.) +/- 0.6 (f(d)/f(s))) x 10(-6).
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: paula.alvarez@cern.ch
Corporate Author Thesis
Publisher (down) 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:000358928400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2324
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title Search for the decay B-s(0) -> (D)over-bar(0) f(0)(980) Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 005 - 19pp
Keywords Hadron-Hadron Scattering; Branching fraction; B physics; Flavor physics
Abstract A search for B-s(0) -> (D) over bar (0) f(0)(980) decays is performed using 3.0 fb(1-) of pp collision data recorded by the LHCb experiment during 2011 and 2012. The f(0)(980) meson is reconstructed through its decay to the pi(+)pi(-) final state in the mass window 900 MeV/c(2) < m (pi(+)pi(-)) < 1080 MeV/c(2). No significant signal is observed. The first upper limits on the branching fraction of B (B-s(0) -> (D) over bar (0) f(0)(980)) < 3.1 (3.4) x 10(-6) are set at 90% (95 %) confidence level.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher (down) 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:000359257300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2366
Permanent link to this record