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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 Observation of the Decay B-s(0) -> K-mu(+)nu(mu) and a Measurement of vertical bar V-ub vertical bar/vertical bar V-cb vertical bar | Type | Journal Article | ||
Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
Volume | 126 | Issue | 8 | Pages | 081804 - 11pp |
Keywords | |||||
Abstract | The first observation of the suppressed semileptonic B-s(0) -> K-mu(+)nu(mu) decay is reported. Using a data sample recorded in pp collisions in 2012 with the LHCb detector, corresponding to an integrated luminosity of 2 fb(-1), the branching fraction B(B-s(0) -> K-mu(+)nu(mu)) is measured to be [1.06 +/- 0.05(stat) +/- 0.08(syst)] x 10(-4), where the first uncertainty is statistical and the second one represents the combined systematic uncertainties. The decay B-s(0) -> D-s(-)mu(+)nu(mu), where D-s(-) is reconstructed in the final state K+K-pi(-), is used as a normalization channel to minimize the experimental systematic uncertainty. Theoretical calculations on the form factors of the B-s(0) -> K- and B-s(0) -> D-s(-) transitions are employed to determine the ratio of the Cabibbo-Kobayashi-Maskawa matrix elements vertical bar V-ub vertical bar/vertical bar V-cb vertical bar at low and high B-s(0) -> K- momentum transfer. | ||||
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 | ||||
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:000621595400003 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4719 | ||
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 | Observation of the Lambda(0)(b) -> Lambda+cK+K-pi(-) decay | Type | Journal Article | ||
Year | 2021 | Publication | Physics Letters B | Abbreviated Journal | Phys. Lett. B |
Volume | 815 | Issue | Pages | 136172 - 10pp | |
Keywords | |||||
Abstract | The Lambda(0)(b) -> Lambda+cK+K-pi(-) decay is observed for the first time using a data sample of proton-proton collisions at centre-of-mass energies of root s = 7 and 8 TeV collected by the LHCb detector, corresponding to an integrated luminosity of 3fb(-1). The ratio of branching fractions between the Lambda(0)(b) -> Lambda K-+(c)+ K-pi(-) and the Lambda(0)(b) -> Lambda D-+(c)s(-) decays is measured to be B(Lambda(0)(b) -> Lambda+cK+K-pi(-))/B(Lambda(0)(b) -> Lambda D-+(c)s(-)) = (9.26 +/- 0.29 +/- 0.46 +/- 0.26) x 10(-2), where the first uncertainty is statistical, the second systematic and the third is due to the knowledge of the D-s(-) -> K+K-pi(-) branching fraction. No structure on the invariant mass distribution of the Lambda K-+(c)+ system is found, consistent with no open-charm pentaquark signature. | ||||
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 | ||||
Corporate Author | Thesis | ||||
Publisher | Elsevier | 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:000632729200049 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4777 | ||
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 CKM angle gamma and Bs0-Bs0bar mixing frequency with Bs0 -> Ds-/+ h +/ pi+/- pi-/+ decays | Type | Journal Article | ||
Year | 2021 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
Volume | 03 | Issue | 3 | Pages | 137 - 46pp |
Keywords | B physics; CKM angle gamma; CP violation; Hadron-Hadron scattering (experiments); Oscillation | ||||
Abstract | The CKM angle gamma is measured for the first time from mixing-induced CP violation between Bs0 -> Ds -/+ K pi +/- pi -/+ and Bs0bar -> Ds +/- K -/+ pi -/+ pi +/- decays reconstructed in proton-proton collision data corresponding to an integrated luminosity of 9 fb(-1) recorded with the LHCb detector. A time-dependent amplitude analysis is performed to extract the CP-violating weak phase gamma – 2 beta (s) and, subsequently, gamma by taking the Bs0-Bs0bar mixing phase beta (s) as an external input. The measurement yields gamma = (44 +/- 12) degrees modulo 180 degrees, where statistical and systematic uncertainties are combined. An alternative model-independent measurement, integrating over the five-dimensional phase space of the decay, yields gamma = (44 -13+20) degrees modulo 180 degrees. Moreover, the Bs0-Bs0bar oscillation frequency is measured from the flavour-specific control channel Bs0 -> Ds- pi+ pi+ pi- to be m(s) = (17.757 +/- 0.007(stat) +/- 0.008(syst)) ps(-1), consistent with and more precise than the current world-average value. | ||||
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 | 1029-8479 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000629837000001 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4760 | ||
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 | Observation of a New Excited D-s(+) Meson in B-0 -> D- D+ K+ pi(-) Decays | Type | Journal Article | ||
Year | 2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
Volume | 126 | Issue | 12 | Pages | 122002 - 11pp |
Keywords | |||||
Abstract | Using pp collision data corresponding to an integrated luminosity of 5.4 fb(-1) collected with the LHCb detector at a center-of-mass energy of 13 TeV, the B-0 -> D- D+ K+ pi(-) decay is studied. A new excited D-s(+) meson is observed decaying into the D+K+pi(-) final state with large statistical significance. The pole mass and width, and the spin parity of the new state are measured with an amplitude analysis to be m(R) = 2591 +/- 6 +/- 7 MeV, Gamma(R) = 89 +/- 16 +/- 12 MeV, and J(P) = 0(-), where the first uncertainty is statistical and the second systematic. Fit fractions for all components in the amplitude analysis are also reported. The new resonance, denoted as D-s0(2590)(+), is a strong candidate to be the D-s(2(1)S(0))(+) state, the radial excitation of the pseudoscalar ground-state D-s(+) meson. | ||||
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 Sicas 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:000646119900007 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4806 | ||
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 the rare decay B-0 -> J/psi phi | Type | Journal Article | ||
Year | 2021 | Publication | Chinese Physics C | Abbreviated Journal | Chin. Phys. C |
Volume | 45 | Issue | 4 | Pages | 043001 - 14pp |
Keywords | B physics; flavour physics; rare decay; omega – phi mixing; branching fraction | ||||
Abstract | A search for the rare decay B-0 -> J/psi phi, is performed using pp collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb(-1). No significant signal of the decay is observed and an upper limit of 1.1 x 10(-7) at 90% confidence level is set on the branching fraction. | ||||
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 | 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 | 1674-1137 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000630745400001 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4751 | ||
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 | Study of B-s(0) -> J/psi pi(+)pi-K+K- decays | Type | Journal Article | ||
Year | 2021 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
Volume | 02 | Issue | 2 | Pages | 024 - 34pp |
Keywords | B physics; Branching fraction; Hadron-Hadron scattering (experiments); Quarkonium; Spectroscopy | ||||
Abstract | The decays B-s(0) -> J/psi pi(+)pi-K+K- are studied using a data set corresponding to an integrated luminosity of 9 fb(-1), collected with the LHCb detector in proton-proton collisions at centre-of-mass energies of 7, 8 and 13TeV. The decays B-s(0) -> J/psi K*(K) over bar *0 and B-s(0) -> chi(c1)(3872)K+K-, where the K+K- pair does not originate from a phi meson, are observed for the first time. Precise measurements of the ratios of branching fractions between intermediate chi(c1)(3872)phi, J/psi K*0 (K) over bar *0, psi(2S)phi and chi(c1)(3872)K+K- states are reported. A structure, denoted as X(4740), is observed in the J/psi phi mass spectrum and, assuming a Breit-Wigner parameterisation, its mass and width are determined to be m(X(4740)) = 4741 +/- 6 +/- 6 MeV/c(2), Gamma(X(4740)) = 53 +/- 15 +/- 11MeV, where the first uncertainty is statistical and the second is systematic. In addition, the most precise single measurement of the mass of the B-s(0) meson is performed and gives a value of m(Bs)(0) = 5366.98 +/- 0.07 +/- 0.13MeV/c(2). | ||||
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: 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 | 1029-8479 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | WOS:000614815700001 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 4731 | ||
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 | Searches for 25 rare and forbidden decays of D+ and Ds+ mesons | Type | Journal Article | ||
Year | 2021 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
Volume | 06 | Issue | 6 | Pages | 044 - 24pp |
Keywords | Charm physics; Flavour physics; Flavour Changing Neutral Currents; Hadron-Hadron scattering (experiments); Rare decay | ||||
Abstract | A search is performed for rare and forbidden charm decays of the form D+-> hl+l -/+, where h(+/-) is a pion or kaon and l((')+/-) is an electron or muon. The measurements are performed using proton-proton collision data, corresponding to an integrated luminosity of 1.6 fb(-1), collected by the LHCb experiment in 2016. No evidence is observed for the 25 decay modes that are investigated and 90 % confidence level limits on the branching fractions are set between 1.4 x 10(-8) and 6.4 x 10(-6). In most cases, these results represent an improvement on existing limits by one to two orders of magnitude. | ||||
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: christopher.burr@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:000762305300001 | Approved | no | ||
Is ISI | yes | International Collaboration | yes | ||
Call Number | IFIC @ pastor @ | Serial | 5158 | ||
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 |