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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 Measurement of the prompt-production cross-section ratio sigma(chi(c2))/sigma(chi(c1)) in pPb collisions at root s(NN)=8.16 TeV Type Journal Article
Year 2021 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume (up) 103 Issue 6 Pages 064905 - 10pp
Keywords
Abstract This article reports the first measurement of prompt chi(c1) and chi(c2) charmonium production in nuclear collisions at Large Hadron Collider energies. The cross-section ratio sigma(chi(c2))/sigma(chi(c1)) is measured in pPb collisions at root s(NN) = 8.16 TeV, collected with the LHCb experiment. The chi(c1,2) states are reconstructed via their decay to a J/psi meson, subsequently decaying into a pair of oppositely charged muons, and a photon, which is reconstructed in the calorimeter or via its conversion in the detector material. The cross-section ratio is consistent with unity in the two considered rapidity regions. Comparison with a corresponding cross-section ratio previously measured by the LHCb Collaboration in pp collisions suggests that chi(c1) and chi(c2) states are similarly affected by nuclear effects occurring in pPb collisions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000661749700003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4872
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 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 (up) 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 (up) 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); Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.
Title Search for CP violation in Xi(-)(b) -> pK(-)K(-) decays Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (up) 104 Issue 5 Pages 052010 - 29pp
Keywords
Abstract A search for CP violation in charmless three-body Xi(-)(b) -> pK(-)K(-) decays is performed using pp collision data recorded with the LHCb detector, corresponding to integrated luminosities of 1 fb(-1) at a center-of-mass energy root S = 7 TeV, 2 fb(-1) at root S = 8 TeV and 2 fb(-1) at = 13 TeV. A good description of the phase-space distribution is obtained with an amplitude model containing contributions from Sigma(1385), Lambda(1405), Lambda(1520), Lambda(1670), Sigma(1775) and Sigma(1915) resonances. The model allows for CP violation effects, which are found to be consistent with zero. The branching fractions of Xi(-)(b) -> Sigma(1385)K-, Xi(-)(b) -> Lambda(1405)K-, Xi(-)(b) -> Lambda(1520)K-, Xi(-)(b) -> Lambda(1670)K-, Xi(-)(b) -> Sigma(1775)K- and Xi(-)(b) -> Sigma(1915)K- decays arc also reported. In addition, an upper limit is placed on the product of ratios of Omega(-)(b) and Xi(-)(b) fragmentation fractions and the Omega(-)(b) -> pK(-)K(-) and Xi(-)(b) -> pK(-)K(-) 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:000704615700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5000
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 excited Omega(0)(c) baryons in Omega(-)(b) -> Xi(+)(c) K-pi(-) decays Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (up) 104 Issue 9 Pages L091102 - 14pp
Keywords
Abstract The first observation of the Omega(-)(b) -> Xi(+)(c) K-pi(-) decay is reported using p p collision data at center of mass energies of 7, 8, and 13 TeV collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb(-1). Four excited Omega(0)(c) baryons are observed in the Xi K-+(c)- mass projection of the Omega(-)(b) -> Xi K-+(c)-pi(-) decays with the significance of each exceeding five standard deviations. They coincide with the states previously observed in prompt pp and e(+)e(-) production. Relative production rates, masses, and natural widths of the states are measured, and a test of spin hypotheses is performed. Moreover, the branching ratio of Omega(-)(b) -> Xi K-+(c)-pi(-) is measured relative to the Omega(-)(b) -> Omega(0)(c)pi(-) decay mode and a precise measurement of the Omega(-)(b) mass of 6044.3 +/- 1.2 +/- 1.1(-0.22)(+0.19) MeV is obtained.
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:000725005800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5045
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 suppressed Lambda(0)(b) -> DpK(-) decay with D -> K+ pi(-) and measurement of its CP asymmetry Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (up) 104 Issue 11 Pages 112008 - 14pp
Keywords
Abstract A study of A(b)(0) baryon decays to the DpK(-) final state is presented based on a proton-proton collision data sample corresponding to an integrated luminosity of 9 fb(-1) collected with the LHCb detector. Two A(b)(0) decays are considered, A(b)(0) -> DpK(-) with D -> K-pi(+) and D -> K+pi(-), where D represents a superposition of D-0 and over bar D-0 states. The latter process is expected to be suppressed relative to the former, and is observed for the first time. The ratio of branching fractions of the two decays is measured, and the CP asymmetry of the suppressed mode, which is sensitive to the Cabibbo-Kobayashi-Maskawa angle gamma, is also reported.
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: daniel.johnson@cern.ch
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:000746362200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5088
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 time-dependent CP violation in D-0 -> K+K- and D-0 -> pi(+)pi(-) decays Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (up) 104 Issue 7 Pages 072010 - 23pp
Keywords
Abstract A search for time-dependent violation of the charge-parity symmetry in D-0 -> K+K- and D-0 -> pi(+)pi(-) decays is performed at the LHCb experiment using proton-proton collision data recorded from 2015 to 2018 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb(-1). The D-0 meson is required to originate from a D*(2010)(+) -> D-0 pi(+) decay, such that its flavor at production is identified by the charge of the accompanying pion. The slope of the time-dependent asymmetry of the decay rates of D-0 and (D) over bar (0) mesons into the final states under consideration is measured to be Delta YK+K- = (-2.3 +/- 1.5 +/- 0.3) x 10(-40), Delta Y pi(+)pi(-) = (-4.0 +/- 2.8 +/- 0.4) x 10(-4), where the first uncertainties are statistical and the second are systematic. These results are compatible with the conservation of the charge-parity symmetry at the level of 2 standard deviations and improve the precision by nearly a factor of 2.
Address [Baptista Leite, J.; Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Torres Machado, D.] 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:000753732900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5119
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 Measurement of the B-s(0) -> mu(+)mu(-) decay properties and search for the B-0 -> mu(+)mu(-) and B-s(0) -> mu(+)mu(-) gamma decays Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (up) 105 Issue 1 Pages 012010 - 34pp
Keywords
Abstract An improved measurement of the decay B-s(0) -> mu(+)mu(-) and searches for the decays B-0 -> mu(+)mu(-) and B-s(0) -> mu(+)mu(-)gamma are performed at the LHCb experiment using data collected in proton-proton collisions at root s = 7, 8 and 13 TeV, corresponding to integrated luminosities of 1, 2 and 6 fb(-1), respectively. The B-s(0) -> mu(+)mu(-) branching fraction and effective lifetime are measured to be B(B-s(0) -> mu(+)mu(-)) = (3.09(-0.43-0.11)(+0.46+0.15)) x 10(-9) and tau(B-s(0) -> mu(+)mu(-)) = (2.07 +/- 0.29 +/- 0.03) ps, respectively, where the uncertain-ties include both statistical and systematic contributions. No significant signal for B-0 -> mu(+)mu(-) and B-s(0) -> mu(+)mu(-) gamma decays is found and the upper limits B(B-0 -> mu(+)mu(-)) < 2.6 x 10(-10) and B(B-s(0) -> mu(+)mu(-)gamma) 2.0 x 10(-9) at 95% confidence level are determined, where the latter is limited to the range m(mu mu) > 4.9 GeV/c(2). Additionally, the ratio between the B-0 -> mu(+)mu(-) and B-s(0) -> mu(+)mu(-) branching fractions is measured to be R mu+mu- < 0.095 at 95% confidence level. The results are in agreement with the 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
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:000754379700009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5126
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 J/psi photoproduction in Pb-Pb peripheral collisions at root S-NN=5 TeV Type Journal Article
Year 2022 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume (up) 105 Issue 3 Pages L032201 - 10pp
Keywords
Abstract The photoproduction of J/psi mesons at low transverse momentum is studied in peripheral lead-lead collisions collected by the LHCb Collaboration at a center-of-mass energy per nucleon pair of 5 TeV, corresponding to an integrated luminosity of 210 μb(-1). The J/psi candidates are reconstructed through the prompt decay into two muons of opposite charge in the rapidity region of 2.0 < y < 4.5. The results significantly improve previous measurements and are compared to the latest theoretical prediction.
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 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000767144000003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5169
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 Measurement of the photon polarization in Lambda(0)(b) -> Lambda gamma decays Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (up) 105 Issue 5 Pages L051104 - 11pp
Keywords
Abstract The photon polarization in b -> s gamma transitions is measured for the first time in radiative b -baryon decays exploiting the unique spin structure of Lambda(0)(b)-> Lambda(gamma) decays. A data sample corresponding to an integrated luminosity of 6 fb(-1) collected by the LHCb experiment in pp collisions at a center-of-mass energy of 13 TeV is used. The photon polarization is measured to be alpha(gamma) = 0.82(-0.26-0.)(13)(+)(0.17+0.04), where the first uncertainty is statistical and the second systematic. This result is in agreement with the Standard Model prediction and previous measurements in b-meson decays. Charge-parity breaking effects are studied for the first time in this observable and found to be consistent with CP symmetry.
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:000788392400005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5219
Permanent link to this record