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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.; 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); 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. | ||||
| Title | Study of coherent J/psi production in lead-lead collisions at root S-NN=5 TeV | Type | Journal Article | ||
| Year | 2022 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
| Volume | 07 | Issue | 7 | Pages | 117 - 19pp |
| Keywords | Heavy Ion Experiments; Particle and Resonance Production; QCD; Quarkonium; Relativistic Heavy Ion Physics | ||||
| Abstract | Coherent production of J/psi mesons is studied in ultraperipheral lead-lead collisions at a nucleon-nucleon centre-of-mass energy of 5 TeV, using a data sample collected by the LHCb experiment corresponding to an integrated luminosity of about 10 μb(-1). The J/psi mesons are reconstructed in the dimuon final state and are required to have transverse momentum below 1 GeV. The cross-section within the rapidity range of 2.0 < y < 4.5 is measured to be 4.45 +/- 0.24 +/- 0.18 +/- 0.58 mb, where the first uncertainty is statistical, the second systematic and the third originates from the luminosity determination. The cross-section is also measured in J/psi rapidity intervals. The results are compared to predictions from phenomenological models. | ||||
| 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: albert.frithjof.bursche@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:000829159300002 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 5309 | ||
| 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 the doubly charmed baryon Xi(+)(cc) | Type | Journal Article | ||
| Year | 2020 | Publication | Science China-Physics Mechanics & Astronomy | Abbreviated Journal | Sci. China-Phys. Mech. Astron. |
| Volume | 63 | Issue | 2 | Pages | 221062 - 15pp |
| Keywords | charmed baryons; limits on production of particles; charmed quarks; experimental tests | ||||
| Abstract | A search for the doubly charmed baryon.+ cc is performed through its decay to the.+ c K- p+ final state, using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV. The data correspond to a total integrated luminosity of 9 fb-1. No significant signal is observed in the mass range from 3.4 to 3.8 GeV/c2. Upper limits are set at 95% credibility level on the ratio of the.+ cc production cross-section times the branching fraction to that of.+ c and.++ cc baryons. The limits are determined as functions of the.+ cc mass for di fferent lifetime hypotheses, in the rapidity range from 2.0 to 4.5 and the transverse momentum range from 4 to 15 GeV/c. | ||||
| 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 |
Science Press | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1674-7348 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000526889100001 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4376 | ||
| 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 | Precise determination of the B-s(0)-B-s(-0) oscillation frequency | Type | Journal Article | ||
| Year | 2022 | Publication | Nature Physics | Abbreviated Journal | Nat. Phys. |
| Volume | 18 | Issue | Pages | 54-58 | |
| Keywords | |||||
| Abstract | Mesons comprising a beauty quark and strange quark can oscillate between particle (B-s(0)) and antiparticle (B-s(-0)) flavour eigenstates, with a frequency given by the mass difference between heavy and light mass eigenstates, Delta m(s). Here we present a measurement of Delta m(s) using B-s(0) -> D-s(-)pi(+) decays produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The oscillation frequency is found to be Delta m(s) = 17.7683 +/- 0.0051 +/- 0.0032 ps(-1), where the first uncertainty is statistical and the second is systematic. This measurement improves on the current Delta m(s) precision by a factor of two. We combine this result with previous LHCb measurements to determine Delta m(s) = 17.7656 +/- 0.0057 ps(-1), which is the legacy measurement of the original LHCb detector. | ||||
| Address | [Aaij, R.; Butter, J. S.; Akiba, K. Carvalho; Sole, S. Ferreres; Gabriel, E.; Geertsema, R. E.; Greeven, L. M.; Heijhoff, K.; Hulsbergen, W.; Hynds, D.; Jans, E.; Klaver, S.; Koppenburg, P.; Kostiuk, I; Kuindersma, H. S.; Martinez, M. Lucio; Lukashenko, V; Mauri, A.; Merk, M.; Pellegrino, A.; Sanchez Gras, C.; Schubiger, M.; Snoch, A.; Tuning, N.; Usachov, A.; van Beuzekom, M.; Veronesi, M.] Nikhef Natl Inst Subatom Phys, Amsterdam, Netherlands, Email: alessandro.bertolin@pd.infn.it | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Nature Portfolio | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1745-2473 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000739810100002 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 5075 | ||
| 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 | Test of lepton universality in beauty-quark decays | Type | Journal Article | ||
| Year | 2022 | Publication | Nature Physics | Abbreviated Journal | Nat. Phys. |
| Volume | 18 | Issue | 3 | Pages | 277-282 |
| Keywords | |||||
| Abstract | The standard model of particle physics currently provides our best description of fundamental particles and their interactions. The theory predicts that the different charged leptons, the electron, muon and tau, have identical electroweak interaction strengths. Previous measurements have shown that a wide range of particle decays are consistent with this principle of lepton universality. This article presents evidence for the breaking of lepton universality in beauty-quark decays, with a significance of 3.1 standard deviations, based on proton–proton collision data collected with the LHCb detector at CERN's Large Hadron Collider. The measurements are of processes in which a beauty meson transforms into a strange meson with the emission of either an electron and a positron, or a muon and an antimuon. If confirmed by future measurements, this violation of lepton universality would imply physics beyond the standard model, such as a new fundamental interaction between quarks and leptons. | ||||
| Address | [Aaij, R.; Butter, J. S.; Akiba, K. Carvalho; Sole, S. Ferreres; Gabriel, E.; Geertsema, R. E.; Greeven, L. M.; Heijhoff, K.; Hulsbergen, W.; Hynds, D.; Jans, E.; Ketel, T.; Klaver, S.; Koppenburg, P.; Kostiuk, I; Kuindersma, H. S.; Martinez, M. Lucio; Lukashenko, V; Mauri, A.; Merk, M.; Pellegrino, A.; Raven, G.; Gras, C. Sanchez; Schubiger, M.; Soares, M. Senghi; Snoch, A.; Tuning, N.; Usachov, A.; Van Beuzekom, M.; Veronesi, M.] Nikhef Natl Inst Subatom Phys, Amsterdam, Netherlands, Email: alessandro.bertolin@pd.infn.it | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Nature Portfolio | Place of Publication | Editor | ||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1745-2473 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000769534600020 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 5166 | ||
| 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 | Measurement of the electron reconstruction efficiency at LHCb | Type | Journal Article | ||
| Year | 2019 | Publication | Journal of Instrumentation | Abbreviated Journal | J. Instrum. |
| Volume | 14 | Issue | Pages | P11023 - 20pp | |
| Keywords | Pattern recognition, cluster finding, calibration and fitting methods; Performance of High Energy Physics Detectors | ||||
| Abstract | The single electron track-reconstruction efficiency is calibrated using a sample corresponding to 1.3 fb(-1) of pp collision data recorded with the LHCb detector in 2017. This measurement exploits B+ -> J/psi (e(+)e(-))K+ decays, where one of the electrons is fully reconstructed and paired with the kaon, while the other electron is reconstructed using only the information of the vertex detector. Despite this partial reconstruction, kinematic and geometric constraints allow the B meson mass to be reconstructed and the signal to be well separated from backgrounds. This in turn allows the electron reconstruction efficiency to be measured by matching the partial track segment found in the vertex detector to tracks found by LHCb's regular reconstruction algorithms. The agreement between data and simulation is evaluated, and corrections are derived for simulated electrons in bins of kinematics. These correction factors allow LHCb to measure branching fractions involving single electrons with a systematic uncertainty below 1%. | ||||
| Address | [Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: laurent.dufour@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:000507589800023 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4253 | ||
| 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 | Measurement of Xi(++)(cc) production in pp collisions at root s=13 TeV | Type | Journal Article | ||
| Year | 2020 | Publication | Chinese Physics C | Abbreviated Journal | Chin. Phys. C |
| Volume | 44 | Issue | 2 | Pages | 022001 - 11pp |
| Keywords | doubly charmed baryons; hadron production; QCD | ||||
| Abstract | The production of Xi(++)(cc) baryons in proton-proton collisions at a centre-of-mass energy of root s = 13 Tev is measured in the transverse-momentum range 4 < p(T) < 15 GeV/c and the rapidity range 2.0 < y < 4.5. The data used in this measurement correspond to an integrated luminosity of 1.7 fb(-1), recorded by the LHCb experiment during 2016. The ratio of the Xi(++)(cc) production cross-section times the branching fraction of the Xi(++)(cc) -> Lambda K-+(c)-pi(+)pi(+) decay relative to the prompt Lambda(+)(c) production cross-section is found to be (2.22 +/- 0.27 +/- 0.29) x 10(-4), assuming the central value of the measured Xi(++)(cc) lifetime, where the first uncertainty is statistical and the second systematic. | ||||
| Address | [Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Torres Machado, D.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil | ||||
| 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:000509923300001 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4268 | ||
| 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 | |||||