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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 | Search for CP violation in D-(s)(+) -> h(+) pi(0) and decays D-(s)(+) -> h(+) eta decays | Type | Journal Article | ||
| Year | 2021 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
| Volume | 06 | Issue | 6 | Pages | 019 - 25pp |
| Keywords | Charm physics; CP violation; Hadron-Hadron scattering (experiments) | ||||
| Abstract | Searches for CP violation in the two-body decays D-(s)(+) -> h(+)pi(0) and D-(s)(+) -> h(+)eta (where h(+) denotes a pi(+) or K+ meson) are performed using pp collision data collected by the LHCb experiment corresponding to either 9 fb(-1) or 6 fb(-1) of integrated luminosity. The pi(0) and eta mesons are reconstructed using the e(+) e(-)gamma final state, which can proceed as three-body decays pi(0) -> e(+) e(-) gamma and eta -> e(+) e(-)gamma, or via the two-body decays pi(0) -> gamma gamma and eta -> gamma gamma followed by a photon conversion. The measurements are made relative to the control modes D-(s)(+) K(S)(0)h(+) to cancel the production and detection asymmetries. The CP asymmetries are measured to be A(CP)(D+ -> pi(+)pi(0)) = (-1.3 +/- 0.9 +/- 0.6)%, A(CP)(D+ -> K+pi(0)) = (- 3.2 +/- 4.7 +/- 2.1)%, A(CP)(D+ -> pi(+)eta) = (-0.2 +/- 0.8 +/- 0.4)%, A(CP)(D+ -> K+eta) = (-6 +/- 10 +/- 4 )%, A(CP)(D-s(+) -> K+pi(0)) = (-0.8 +/- 3.9 +/- 1.2)%, A(CP)(D-s(+) -> pi(+)eta) = ( 0.8 +/- 0.7 +/- 0.5)%, A(CP)(D-s(+) -> K+eta) = ( 0.9 +/- 3.7 +/- 1.1)%, where the first uncertainties are statistical and the second systematic. These results are consistent with no CP violation and mostly constitute the most precise measurements of A(CP) in these decay modes 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, Email: tom.hadavizadeh@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:000658752200001 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4849 | ||
| 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 | Angular analysis of B0 -> D*- D*s+ with D*s+ -> Ds + gamma decays | Type | Journal Article | ||
| Year | 2021 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
| Volume | 06 | Issue | 6 | Pages | 177 - 30pp |
| Keywords | B physics; Branching fraction; Hadron-Hadron scattering (experiments); Polarization | ||||
| Abstract | The first full angular analysis of the B0 -> D-Ds+ decay is performed using 6 fb(-1) of pp collision data collected with the LHCb experiment at a centre-of-mass energy of 13 TeV. The Ds+-> Ds+gamma and D*- -> D<overbar></mml:mover>0- vector meson decays are used with the subsequent Ds+ -> K+K-pi (+) and D<overbar></mml:mover>0 -> K+pi (-) decays. All helicity amplitudes and phases are measured, and the longitudinal polarisation fraction is determined to be f(L) = 0.578 +/- 0.010 +/- 0.011 with world-best precision, where the first uncertainty is statistical and the second is systematic. The pattern of helicity amplitude magnitudes is found to align with expectations from quark-helicity conservation in B decays. The ratio of branching fractions [B(B0 -> D-Ds+) x B(Ds+-> Ds+gamma)]/B(B-0 -> D(*-)Ds+) is measured to be 2.045 +/- 0.022 +/- 0.071 with world-best precision. In addition, the first observation of the Cabibbo-suppressed B-s -> D(*-)Ds+ decay is made with a significance of seven standard deviations. The branching fraction ratio B(B-s -> D(*-)Ds<mml:mo>+)/B(B-0 -> D(*-)Ds<mml:mo>+) is measured to be 0.049 +/- 0.006 +/- 0.003 +/- 0.002, where the third uncertainty is due to limited knowledge of the ratio of fragmentation fractions.<fig id=“Figa” position=“anchor”><graphic position=“anchor” specific-use=“HTML” mime-subtype=“JPEG” xmlns:xlink=“http://www.w3.org/1999/xlink” xlink:href=“MediaObjects/13130202116089FigaHTML.jpg” id=“MO1”></graphic | ||||
| Address | [Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Robbe, P.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: donal.hill@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:000671168600002 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4890 | ||
| 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 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 | ||
| Year | 2021 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
| Volume | 10 | Issue | 10 | Pages | 060 - 38pp |
| Keywords | Hadron-Hadron scattering (experiments); Heavy quark production; proton-proton scattering; Hard scattering; B physics | ||||
| 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. | ||||
| 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 | ||||
| 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:000705235400002 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 4985 | ||
| 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 | Angular analysis of the rare decay B-s(0) -> phi mu(+)mu(-) | Type | Journal Article | ||
| Year | 2021 | Publication | Journal of High Energy Physics | Abbreviated Journal | J. High Energy Phys. |
| Volume | 11 | Issue | 11 | Pages | 043 - 45pp |
| Keywords | B physics; FCNC Interaction; Flavor physics; Hadron-Hadron scattering (experiments); Rare decay | ||||
| Abstract | An angular analysis of the rare decay B-s(0) -> phi mu(+)mu(-) is presented, using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13TeV, corresponding to an integrated luminosity of 8.4 fb(-1). The observables describing the angular distributions of the decay B-s(0) -> phi mu(+)mu(-) are determined in regions of q(2), the square of the dimuon invariant mass. The results are consistent with Standard Model predictions. | ||||
| 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: marcel.materok@rwth-aachen.de | ||||
| 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:000716428600002 | Approved | no | ||
| Is ISI | yes | International Collaboration | yes | ||
| Call Number | IFIC @ pastor @ | Serial | 5018 | ||
| Permanent link to this record | |||||