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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. |
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Title |
Measurement of the J/psi pair production cross-section in pp collisions at root s=13 TeV |
Type |
Journal Article |
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Year |
2017 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
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Volume |
06 |
Issue |
6 |
Pages |
047 - 38pp |
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Keywords |
Hadron-Hadron scattering (experiments); Particle and resonance production; proton-proton scattering; QCD; Quarkonium |
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Abstract |
The production cross-section of J/psi pairs is measured using a data sample of pp collisions collected by the LHCb experiment at a centre-of-mass energy of root s = 13TeV, corresponding to an integrated luminosity of 279 +/- 11 pb(-1). The measurement is performed for J/psi mesons with a transverse momentum of less than 10 GeV/c in the rapidity range 2.0 < y < 4.5. The production cross-section is measured to be 15.2 +/- 1.0 +/- 0.9 nb. The first uncertainty is statistical, and the second is systematic. The differential cross-sections as functions of several kinematic variables of the J/psi pair are measured and compared to theoretical predictions. |
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Address |
[Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Molina Rodriguez, J.; dos Reis, A. C.; Rodrigues, A. B.; Salustino Guimaraes, V.; Soares Lavra, I.] CBPF, Rio De Janeiro, Brazil |
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Springer |
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English |
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ISSN |
1029-8479 |
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Conference |
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Notes |
WOS:000402990000004 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3367 |
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Author |
LHCb Collaboration (Aaij, R. et al); Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. |
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Title |
Observation of a Lambda(0)(b) – (Lambda)over-bar(b)(0) production asymmetry in proton-proton collisions at root s=7 and 8 TeV |
Type |
Journal Article |
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Year |
2021 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
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Volume |
10 |
Issue |
10 |
Pages |
060 - 38pp |
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Keywords |
Hadron-Hadron scattering (experiments); Heavy quark production; proton-proton scattering; Hard scattering; B physics |
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Abstract |
This article presents differential measurements of the asymmetry between Lambda(0)(b) and (Lambda) over bar (0)(b) baryon production rates in proton-proton collisions at centre-of-mass energies of root s = 7 and 8 TeV collected with the LHCb experiment, corresponding to an integrated luminosity of 3 fb(-1). The Lambda(0)(b) baryons are reconstructed through the inclusive semileptonic decay Lambda(0)(b) -> Lambda(+)(c) mu(-)(nu) over bar X-mu. The production asymmetry is measured both in intervals of rapidity in the range 2:15 < y < 4:10 and transverse momentum in 2 < p T < 27 GeV/c. The results are found to be incompatible with symmetric production with a significance of 5.8 standard deviations for both root s = 7 and 8 TeV data, assuming no CP violation in the decay. There is evidence for a trend as a function of rapidity with a significance of 4 standard deviations. Comparisons to predictions from hadronisation models in Pythia and heavy-quark recombination are provided. This result constitutes the first observation of a particle-antiparticle asymmetry in b-hadron production at LHC energies. |
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Address |
[Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: sascha.stahl@cern.ch |
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Springer |
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English |
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Series Volume |
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ISSN |
1029-8479 |
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Expedition |
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Conference |
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Notes |
WOS:000705235400002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4985 |
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Author |
LHCb Collaboration (Aaij, R. et al); Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanderswood, I. |
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Title |
Observation of the doubly charmed baryon decay Xi(++)(cc) -> Xi(c)'(+)pi(+) |
Type |
Journal Article |
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Year |
2022 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
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Volume |
05 |
Issue |
5 |
Pages |
038 - 18pp |
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Keywords |
Charm Physics; Flavour Physics; Hadron-Hadron Scattering; Proton-Proton Scattering |
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Abstract |
The Xi(++)(cc) -> Xi('+)(c)pi(+) decay is observed using proton-proton collisions collected by the LHCb experiment at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 fb(-1). The Xi(++)(cc) -> Xi('+)(c)pi(+) decay is reconstructed partially, where the photon from the Xi('+)(c) -> Xi(+)(c)gamma decay is not reconstructed and the pK(-)pi(+) final state of the Sc+ baryon is employed. The Xi(++)(cc) -> Xi('+)(c)pi(+) branching fraction relative to that of the Xi(++)(cc) -> Xi('+)(c)pi(+) decay is measured to be 1.41 +/- 0.17 +/- 0.10, where the first uncertainty is statistical and the second systematic. |
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Address |
[Baptista de Souza Leite, J.; Bediaga, I.; Cruz Torres, M.; De Freitas Carneiro Da Graca, U.; De Miranda, J. M.; dos Reis, A. C.; Falcao, L. N.; Gomes, A.; Massafferri, A.; Torres Machado, D.] Ctr Brasileiro Pesquisas Fisicas CBPF, Rio De Janeiro, Brazil, Email: wenqian.huang@cern.ch |
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Springer |
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English |
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ISSN |
1029-8479 |
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Conference |
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Notes |
WOS:000793847800001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5226 |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
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Title |
Measurement of forward Z -> e(+)e(-) production at root s=8 TeV |
Type |
Journal Article |
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Year |
2015 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
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Volume |
05 |
Issue |
5 |
Pages |
109 - 21pp |
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Keywords |
Electroweak interaction; QCD; Forward physics; Hadron-Hadron Scattering; proton-proton scattering |
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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. |
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Address |
CBPF, Rio De Janeiro, Brazil, Email: drw1@cam.ac.uk |
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Publisher |
Springer |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Expedition |
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Conference |
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Notes |
WOS:000354977800001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
2236 |
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| Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
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Title |
Measurement of the forward Z boson production cross-section in pp collisions at root s=7 TeV |
Type |
Journal Article |
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Year |
2015 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
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Volume |
08 |
Issue |
8 |
Pages |
039 - 37pp |
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Keywords |
Electroweak interaction; Hadron-Hadron Scattering; proton-proton scattering; QCD; Forward physics |
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Abstract |
A measurement of the production cross-section for Z bosons that decay to muons is presented. The data were recorded by the LHCb detector during pp collisions at a centre-of-mass energy of 7 TeV, and correspond to an integrated luminosity of 1.0 fb(-1). The cross-section is measured for muons in the pseudorapidity range 2.0 < eta < 4.5 with transverse momenta p(T) >20 GeV/e. The dimuon mass is restricted to 60 < M mu+mu- < 120 GeV/c(2). The measured cross-section is sigma(Z ->mu+mu-) = (76.0 +/- 0.3 +/- 0.5 +/- 1.0 +/- 1.3) pb where the uncertainties are due to the sample size, systematic effects, the beam energy and the luminosity. This result is in good agreement with theoretical predictions at next-to-next-to-leading order in perturbative quantum chromodynamics. The cross-section is also measured differentially as a function of kinematic variables of the Z boson. Ratios of the production cross-sections of electroweak bosons are presented using updated LHCb measurements of W boson production. A precise test of the Standard Model is provided by the measurement of the ratio sigma(W+) -> mu(+) nu(mu) + sigma(W) -> mu(+) (nu) over bar (mu)/sigma(Z ->mu+mu-) = 0.09 +/- 0.12 +/- 0.05, where the uncertainty due to luminosity cancels. |
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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: ronan.wallace@cern.ch |
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Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Expedition |
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Conference |
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Notes |
WOS:000363518700002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
2439 |
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