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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 | Precise measurement of the f(s)/f(d) ratio of fragmentation fractions and of B-s(0) decay branching fractions | Type | Journal Article | ||
Year  |
2021 | Publication | Physical Review D | Abbreviated Journal | Phys. Rev. D |
| Volume | 104 | Issue | 3 | Pages | 032005 - 20pp |
| Keywords | |||||
| Abstract | The ratio of the B-s(0) and B-0 fragmentation fractions, f(s)/f(d), in proton-proton collisions at the LHC, is obtained as a function of B-meson transverse momentum and collision center-of-mass energy from the combined analysis of different B-decay channels measured by the LHCb experiment. The results are described by a linear function of the meson transverse momentum or with a function inspired by Tsallis statistics. Precise measurements of the branching fractions of the B-s(0) -> J/psi phi and B-s(0)-> D-s(-)pi(+) decays are performed, reducing their uncertainty by about a factor of 2 with respect to previous world averages. Numerous B-s(0) decay branching fractions, measured at the LHCb experiment, are also updated using the new values of f(s)/f(d) and branching fractions of normalization channels. These results reduce a major source of systematic uncertainty in several searches for new physics performed through measurements of B-s(0) branching fractions. | ||||
| 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 | 2470-0010 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000686913600001 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4947 | ||
| 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 CP asymmetry in D-0 -> KS0 KS0 decays | Type | Journal Article | ||
| Year |
2021 | Publication | Physical Review D | Abbreviated Journal | Phys. Rev. D |
| Volume | 104 | Issue | 3 | Pages | L031102 - 11pp |
| Keywords | |||||
| Abstract | A measurement of the CP asymmetry in D-0 -> (KSKS0)-K-0 decays is reported, based on a data sample of proton-proton collisions collected by the LHCb experiment from 2015 to 2018, corresponding to an integrated luminosity of 6 fb(-1). The flavor of the D-0 candidate is determined using the charge of the D-*+/- meson, from which the decay is required to originate. The D-0 -> K+K- decay is used as a calibration channel. The time-integrated CP asymmetry for the D-0 -> (KSKS0)-K-0 mode is measured to be A(CP)(D-0 -> (KSKS0)-K-0) = (-3.1 +/- 1.2 +/- 0.4 +/- 0.2), where the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty on the CP asymmetry of the calibration channel. This is the most precise determination of this quantity to date. | ||||
| 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 | 2470-0010 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | WOS:000692072800012 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4954 | ||
| 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); Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. | ||||
| Title | Observation of the Mass Difference Between Neutral Charm-Meson Eigenstates | Type | Journal Article | ||
| Year |
2021 | Publication | Physical Review Letters | Abbreviated Journal | Phys. Rev. Lett. |
| Volume | 127 | Issue | 11 | Pages | 111801 - 12pp |
| Keywords | |||||
| Abstract | A measurement of mixing and CP violation in neutral charm mesons is performed using data reconstructed in proton-proton collisions collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4 fb(-1). A total of 30.6 million D0 -> K-s(0)pi(+)pi(-) decays are analyzed using a method optimized for the measurement of the mass difference between neutral charmmeson eigenstates. Allowing for CP violation in mixing and in the interference between mixing and decay, the mass and decay-width differences are measured to be x(CP) = [3.97 +/- 0.46(stat) +/- 0.29(syst)] x 10(-3) and y(CP) = [4.59 +/- 1.20(stat) +/- 0.85(syst)] x 10(-3), respectively. The CP-violating parameters are measured as Delta x= [-0.27 +/- 0.18(stat)+/- 0.01(syst)] x 10 (-3) and Delta y = [0.20 +/- 0.36(stat) +/- 0.13(syst)] x 10(-3). This is the first observation of a nonzero mass difference in the D-0 meson system, with a significance exceeding seven standard deviations. The data are consistent with CP symmetry and improve existing constraints on the associated parameters. | ||||
| 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:000693639800004 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4965 | ||
| 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 the doubly charmed baryon Omega(+)(cc) | Type | Journal Article | ||
| Year |
2021 | Publication | Science China-Physics Mechanics & Astronomy | Abbreviated Journal | Sci. China-Phys. Mech. Astron. |
| Volume | 64 | Issue | 10 | Pages | 101062 - 12pp |
| Keywords | charmed baryons; limits on production of particles; charmed quarks; experimental tests | ||||
| Abstract | A search for the doubly charmed baryon Omega(+)(cc) with the decay mode Omega(+)(cc) -> Xi K-+(c)-pi(+) is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4 fb(-1). No significant signal is observed within the invariant mass range of 3.6 to 4.0GeV/c(2). Upper limits are set on the ratio R of the production cross-section times the total branching fraction of the Omega(+)(cc) -> Xi K-+(c)-pi(+) decay with respect to the Xi(++)(cc) -> Lambda K-+(c)-pi(+)pi(+) decay. Upper limits at 95% credibility level for R in the range 0.005 to 0.11 are obtained for different hypotheses on the Omega(+)(cc) mass and lifetime in the rapidity range from 2.0 to 4.5 and transverse momentum range from 4 to 15 GeV/c. | ||||
| Address | [Baptista Leite, J.; Bediaga, I; Cruz Torres, 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 | ||||
| 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:000694853300003 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4971 | ||
| Permanent link to this record | |||||