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Author | LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. | ||||
Title | Measurement of the eta(c)(1S) production cross-section in p p collisions at root s=13TeV | Type | Journal Article | ||
Year | 2020 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 80 | Issue | 3 | Pages | 191 - 18pp |
Keywords | |||||
Abstract | Using a data sample corresponding to an integrated luminosity of 2.0 fb-1, collected by the LHCb experiment, the production of the.c(1S) state in proton-proton collisions at a centre-of-mass energy of v s = 13 TeVis studied in the rapidity range 2.0 < y < 4.5 and in the transverse momentum range 6.5 < pT < 14.0GeV. The cross-section for prompt production of.c(1S) mesons relative to that of the J/. meson is measured using the p p decay mode and is found to be s.c(1S)/sJ/. = 1.69 +/- 0.15 +/- 0.10 +/- 0.18. The quoted uncertainties are, in order, statistical, systematic and due to uncertainties on the branching fractions of the J/.. p p and.c. p p decays. The prompt.c(1S) production cross-section is determined to be s.c( 1S) = 1.26 +/- 0.11 +/- 0.08 +/- 0.14 μb, where the last uncertainty includes that on the J/. meson cross-section. The ratio of the branching fractions of b-hadron decays to the.c(1S) and J/. states is measured to be Bb..c X /Bb. J/. X = 0.48 +/- 0.03 +/- 0.03 +/- 0.05, where the last uncertainty is due to those on the branching fractions of the J/.. p p and.c. p p decays. The difference between the J/. and.c(1S) masses is also determined to be 113.0 +/- 0.7 +/- 0.1MeV, which is the most precise single measurement of this quantity to date. | ||||
Address | [Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, L.] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: andrii.usachov@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 | 1434-6044 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000528546600004 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4398 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. | ||||
Title | Search for CP violation in Xi(+)(c) -> pK(-) pi(+) decays using model-independent techniques | Type | Journal Article | ||
Year | 2020 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 80 | Issue | 10 | Pages | 986 - 16pp |
Keywords | |||||
Abstract | A first search for CP violation in the Cabibbo-suppressed Xi(+)(c) -> pK(-) pi(+) decay is performed using both a binned and an unbinned model-independent technique in the Dalitz plot. The studies are based on a sample of protonproton collision data, corresponding to an integrated luminosity of 3.0 fb(-1), and collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The data are consistent with the hypothesis of no CP violation. | ||||
Address | [Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil, Email: maria.vieites.diaz@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 | 1434-6044 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000588331200001 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4604 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. | ||||
Title | Search for heavy neutral leptons in W plus . μplus μ+/- jet decays | Type | Journal Article | ||
Year | 2021 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 81 | Issue | 3 | Pages | 248 - 15pp |
Keywords | |||||
Abstract | A search is performed for heavy neutrinos in the decay of a W boson into two muons and a jet. The data set corresponds to an integrated luminosity of approximately 3.0 fb-1 of proton-proton collision data at centre-of-mass energies of 7 and 8 TeV collected with the LHCb experiment. Both same-sign and opposite-signmuons in the final state are considered. Data are found to be consistent with the expected background. Upper limits on the coupling of a heavy neutrino with the Standard Model neutrino are set at 95% confidence level in the heavy-neutrino mass range from 5 to 50GeV/c2. These are of the order of 10(-3) for lepton-number-conserving decays and of the order of 10(-4) for lepton-number-violating heavy-neutrino decays. | ||||
Address | [Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil, Email: maria.vieites.diaz@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 | 1434-6044 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000631882200001 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4755 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
Title | Search for long-lived particles decaying to e(+/-)mu(-/+)nu | Type | Journal Article | ||
Year | 2021 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 81 | Issue | 3 | Pages | 261 - 16pp |
Keywords | |||||
Abstract | Long-lived particles decaying to e(+/-) mu(-/+)nu, with masses between 7 and 50 GeV/c(2) and lifetimes between 2 and 50 ps, are searched for by looking at displaced vertices containing electrons and muons of opposite charges. The search is performed using 5.4 fb(-1) of pp collisions collected with the LHCb detector at a centre-of-mass energy of root s = 13 TeV. Three mechanisms of production of long-lived particles are considered: the direct pair production from quark interactions, the pair production from the decay of a Standard-Model-like Higgs boson with a mass of 125 GeV/c(2), and the charged current production from an on-shell W boson with an additional lepton. No evidence of these long-lived states is obtained and upper limits on the production cross-section times branching fraction are set on the different production modes. | ||||
Address | [Amato, S.; De Paula, L.; Rodrigues, F. Ferreira; Gandelman, M.; Hicheur, A.; Lopes, J. H.; Garcia, L. Meyer; Nasteva, I; Goicochea, J. M. Otalora; Polycarpo, E.; Rangel, M. S.; De Almeida, F. L. Souza; De Paula, B. Souza] Univ Fed Rio de Janeiro UFRJ, Rio De Janeiro, Brazil, Email: matthieu.marinangeli@gmail.com | ||||
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:000634800600002 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4771 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
Title | Measurement of the branching fraction of the B0 -> Ds+ pi- decay | Type | Journal Article | ||
Year | 2021 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 81 | Issue | 4 | Pages | 314 - 15pp |
Keywords | |||||
Abstract | A branching fraction measurement of the B0 -> Ds+</mml:msubsup>pi- decay is presented using proton-proton collision data collected with the LHCb experiment, corresponding to an integrated luminosity of 5.0<mml:mspace width=“0.166667em”></mml:mspace>fb-1. The branching fraction is found to be B(B0 -> Ds+</mml:msubsup>pi-)=(19.4 +/- 1.8 +/- 1.3 +/- 1.2)x10-6, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the B0 -> D-pi+, Ds+</mml:msubsup>-> K+K-pi+ and D--> K+pi-pi- branching fractions. This is the most precise single measurement of this quantity to date. As this decay proceeds through a single amplitude involving a b -> u charged-current transition, the result provides information on non-factorisable strong interaction effects and the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element <mml:msub>Vub. Additionally, the collision energy dependence of the hadronisation-fraction ratio <mml:msub>fs/<mml:msub>fd is measured through B<overbar></mml:mover>s0 -> Ds+pi- and B0 -> D-pi <mml:mo>+ decays. | ||||
Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: michel.de.cian@cem.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 | 1434-6044 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000639810800004 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4800 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. | ||||
Title | Observation of new excited Bs0 states | Type | Journal Article | ||
Year | 2021 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 81 | Issue | 7 | Pages | 601 - 11pp |
Keywords | |||||
Abstract | A structure is observed in the B +/- K -/+ mass spectrum in a sample of proton-proton collisions at centre-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of 9 fb-1. The structure is interpreted as the result of overlapping excited Bs0</mml:msubsup> states. With high significance, a two-peak hypothesis provides a better description of the data than a single resonance. Under this hypothesis the masses and widths of the two states, assuming they decay directly to B +/- K -/+, are determined to be m1 = 6063.5 +/- 1.2 (stat) +/- 0.8 (syst) MeV Gamma 1 = 26 +/- 4 (stat) +/- 4 (syst) MeV m2 = 6114 +/- 3 (stat) +/- 5 (syst) MeV Gamma 2 = 66 +/- 18 (stat) +/- 21 (syst) MeV Alternative values assuming a decay through B +/- K -/+, with a missing photon from the B +/- -> B +/- gamma decay, which are shifted by approximately 45 MeV, are also determined. The possibility of a single state decaying in both channels is also considered. The ratio of the total production cross-section times branching fraction of the new states relative to the previously observed Bs20 state is determined to be 0.87 +/- 0.15 (stat)+/- 0.19 (syst). |
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Address | [Leite, J. Baptista; Bediaga, I.; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Kucewicz, W.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fisicas CBPF, Rio De Janeiro, Brazil | ||||
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:000691564500002 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4957 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
Title | First measurement of the CP-violating phase in B-s(0) -> J/Psi (-> e(+) e(-))phi decays | Type | Journal Article | ||
Year | 2021 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 81 | Issue | 11 | Pages | 1026 - 18pp |
Keywords | |||||
Abstract | A flavour-tagged time-dependent angular analysis of B-s(0) -> J/Psi phi decays is presented where the J/Psi meson is reconstructed through its decay to an e(+)e(-) pair. The analysis uses a sample of pp collision data recorded with the LHCb experiment at centre-of-mass energies of 7 and 8TeV, corresponding to an integrated luminosity of 3 fb(-1). The CP-violating phase and lifetime parameters of the B-s(0) s system are measured to be phi(s) = 0.00 +/- 0.28 +/- 0.07 rad, Delta Gamma(s) = 0.115 +/- 0.045 +/- 0.011 ps(-1) and Delta Gamma(s) = 0.608 +/- 0.018 +/- 0.012 ps(-1) where the first uncertainty is statistical and the second systematic. This is the first time that CP-violating parameters are measured in the B-s(0) -> J/Psi phi decay with an e+e- pair in the final state. The results are consistent with previous measurements in other channels and with the Standard Model predictions. | ||||
Address | [Leite, J. Baptista; Bediaga, I; CruzTorres, M.; 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: varvara.batozskaya@ncbj.gov.pl; | ||||
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:000722225100003 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 5033 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
Title | Search for massive long-lived particles decaying semileptonically at root s=13 TeV | Type | Journal Article | ||
Year | 2022 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 82 | Issue | 4 | Pages | 373 - 19pp |
Keywords | |||||
Abstract | A search is performed for massive long-lived particles (LLPs) decaying semileptonically into a muon and two quarks. Two kinds of LLP production processes were considered. In the first, a Higgs-like boson with mass from 30 to 200 GeV/c(2) is produced by gluon fusion and decays into two LLPs. The analysis covers LLP mass values from 10 GeV/c(2) up to about one half the Higgs-like boson mass. The second LLP production mode is directly from quark interactions, with LLP masses from 10 to 90 GeV/c(2). The LLP lifetimes considered range from 5 to 200 ps. This study uses LHCb data collected from proton-proton collisions at root s = 13 TeV, corresponding to an integrated luminosity of 5.4 fb(-1). No evidence of these long-lived states has been observed, and upper limits on the production cross-section times branching ratio have been set for each model considered. | ||||
Address | [LHCb Collaboration] CERN, CH-1211 Geneva 23, Switzerland, Email: aurelio.bay@epfl.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 | 1434-6044 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000788631800002 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 5213 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Jaimes Elles, S.J.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Rebollo De Miguel, M.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanderswood, I. | ||||
Title | J/ψ and D0 production in √s_NN=68.5 GeV PbNe collisions | Type | Journal Article | ||
Year | 2023 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 83 | Issue | 7 | Pages | 658 - 11pp |
Keywords | |||||
Abstract | The firstmeasurement of J/psi and D-0 production in PbNe collisions by the LHCb experiment in its fixed-target configuration is reported. The production of J/psi and D-0 mesons is studied with a beam of lead ions with an energy of 2.5 TeV per nucleon colliding on gaseous neon targets at rest, corresponding to a nucleon-nucleon centre-of-mass energy of root s(NN) = 68.5 GeV. The J/psi/D-0 production crosssection ratio is studied as a function of rapidity, transverse momentum and collision centrality. These data are compared with measurements from pNe collisions at the same energy and showno difference in the observed J/psi suppression trend when comparing pNe and PbNe peripheral collisions with PbNe central collisions. | ||||
Address | [Leite, J. Baptista de Souza; Bediaga, I. B.; Torres, M. Cruz; Da Graca, U. De Freitas Carneiro; De Miranda, J. M.; dos Reis, A. C.; Falcao, L. N.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil | ||||
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:001062058800003 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 5772 | ||
Permanent link to this record | |||||
Author | LHCb Collaboration (Aaij, R. et al); Jaimes Elles, S.J.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Rebollo De Miguel, M.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanderswood, I.; Zhuo, J. | ||||
Title | Search for D*(2007)0 → μ+ μ- in B- → π- μ+ μ- decays | Type | Journal Article | ||
Year | 2023 | Publication | European Physical Journal C | Abbreviated Journal | Eur. Phys. J. C |
Volume | 83 | Issue | 7 | Pages | 666 - 14pp |
Keywords | |||||
Abstract | The very rare D*(2007)(0) -> mu(+) mu(-) decay is searched for by analysing B- -> pi (-) mu(+) mu(-) decays. The analysis uses a sample of beautymesons produced in protonproton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9 fb(-1). The signal signature corresponds to simultaneous peaks in the mu(+) mu(-) and pi(-) mu(+) mu(-) invariant masses. No evidence for an excess of events over background is observed and an upper limit is set on the branching fraction of the decay at B(D-*(2007)(0) -> mu(+) mu(-)) < 2.6 x 10(-8) at 90% confidence level. This is the first limit on the branching fraction of D*(2007)(0) -> mu(+) mu(-) decays and the most stringent limit on D* (2007)(0) decays to leptonic final states. The analysis is the first search for a rare charm-meson decay exploiting production via beauty decays. | ||||
Address | [Baptista de Souza Leite, J.; Bediaga, I. B.; 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 Fis, Rio De Janeiro, Brazil, Email: juan.baptista.leite@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 | 1434-6044 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:001062453500001 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 5816 | ||
Permanent link to this record |