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Author LHCb Collaboration (Aaij, R. et al); Jaimes Elles, S.J.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Rebollo De Miguel, M.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanderswood, I.
Title (down) Λc+ polarimetry using the dominant hadronic mode Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 228 - 26pp
Keywords Polarization; Charm Physics; Flavour Physics; Hadron-Hadron Scattering
Abstract The polarimeter vector field for multibody decays of a spin-half baryon is introduced as a generalisation of the baryon asymmetry parameters. Using a recent amplitude analysis of the Lambda(+)(c) -> pK(-)pi(+) decay performed at the LHCb experiment, we compute the distribution of the kinematic-dependent polarimeter vector for this process in the space of Mandelstam variables to express the polarised decay rate in a model-agnostic form. The obtained representation can facilitate polarisation measurements of the Lambda(+)(c) baryon and eases inclusion of the Lambda(+)(c)-> pK(-)pi(+) decay mode in hadronic amplitude analyses.
Address [Leite, J. Baptista de Souza; Bediaga, I. B.; Torres, M. Cruz; Da Graca, U. De Freitas Carneiro; De Miranda, J. M.; dos Reis, A. C.; Falcao, L. N.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis, 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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001062420200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5771
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title (down) Updated search for long-lived particles decaying to jet pairs Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 12 Pages 812 - 14pp
Keywords
Abstract A search is presented for long-lived particles with a mass between 25 and 50 GeV/c(2) and a lifetime between 2 and 500 ps, using proton-proton collision data corresponding to an integrated luminosity of 2.0 fb(-1), collected by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. The particles are assumed to be pair-produced in the decay of a 125 GeV/c(2) Standard-Model-like Higgs boson. The experimental signature is a single long-lived particle, identified by a displaced vertex with two associated jets. No excess above background is observed and limits are set on the production cross-section as a function of the mass and lifetime of the long-lived particle.
Address [LHCb Collaboration] CERN, CH-1211 Geneva 23, Switzerland
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:000417101000002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3399
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 (down) Updated search for B-c(+) decays to two charm mesons Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 12 Issue 12 Pages 117 - 23pp
Keywords B physics; Branching fraction; Flavor physics; Hadron-Hadron scattering (experiments)
Abstract A data set corresponding to an integrated luminosity of 9 fb(-1) of proton-proton collisions collected by the LHCb experiment has been analysed to search for D-(s)(()*())+ ((D) over bar)(*)0 decays. The decays are fully or partially reconstructed, where one or two (8) missing neutral pions or photons from the decay of an excited charm meson are allowed. Upper limits for the branching fractions, normalised to B+ decays to final states with similar topologies, are obtained for sixteen B-c(+) decay modes. For the decay B-c(+) -> D-s(+)(D) over bar (0), an excess with a significance of 3.4 standard deviations is found.
Address [Baptista Leite, J.; Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, C.; Gomes, A.; Massafferri, A.; Torres Machado, D.] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: fionn.caitlin.ros.bishop@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:000732953900003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5056
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 (down) Updated measurement of time-dependent CP-violating observables in B-s(0) -> J/psi K+K- decays Type Journal Article
Year 2019 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 79 Issue 8 Pages 706 - 26pp
Keywords
Abstract The decay-time-dependent CP asymmetry in B0 s. J/. K + K-decays is measured using proton-proton collision data, corresponding to an integrated luminosity of 1.9 fb-1, collected with the LHCb detector at a centre-ofmass energy of 13 TeV in 2015 and 2016. Using a sample of approximately 117 000 signal decays with an invariant K + K-mass in the vicinity of the f( 1020) resonance, the CP-violating phase fs is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the B0 s-B0s system, s. The difference of the average B0 s and B0 meson decay widths, s-d, is determined using in addition a sample of B0. J/. K + p-decays. The values obtained are fs =-0.083 +/- 0.041 +/- 0.006 rad, s = 0.077 +/- 0.008 +/- 0.003 ps-1 and s-d = -0.0041 +/- 0.0024 +/- 0.0015 ps-1, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements of these quantities to date and are consistent with expectations based on the Standard Model and with a previous LHCb analysis of this decay using data recorded at centre-of-mass energies 7 and 8 TeV. Finally, the results are combined with recent results from B0 s. J/. p + p-decays obtained using the same dataset as this analysis, and with previous independent LHCb results.
Address [Bediaga, I.; Torres, M. Cruz; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Reis, A. C. dos; Lavra, l. Soares] Ctr Brasileiro Pesquisas Fisicas CBPF, Rio De Janeiro, Brazil, Email: veronika.chobanova@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:000482401700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4121
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Ruiz Vidal, J.; Sanchez Mayordomo, C.
Title (down) Updated determination of D-0-(D)over-bar(0) mixing and CP violation parameters with D-0 -> K+ pi(-) decays Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 97 Issue 3 Pages 031101 - 11pp
Keywords
Abstract We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D-0 -> K+pi(-) to D-0 -> K-pi(+) rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of 5.0 fb(-1) recorded by the LHCb experiment from 2011 through 2016. Assuming charge-parity (CP) symmetry, the mixing parameters are determined to be x'(2) = (3.9 +/- 2.7) x 10(-5), y' = (5.28 +/- 0.52) x 10(-3), and R-D = (3.454 +/- 0.031) x 10(-3). Without this assumption, the measurement is performed separately for D-0 and (D) over bar (0) mesons, yielding a direct CP-violating asymmetry A(D) = (-0.1 +/- 9.1) x 10(-3), and magnitude of the ratio of mixing parameters 1.00 < vertical bar q/p vertical bar < 1.35 at the 68.3% confidence level. All results include statistical and systematic uncertainties and improve significantly upon previous single-measurement determinations. No evidence for CP violation in charm mixing is observed.
Address [Bediaga, I.; Torres, M. Cruz; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Lavra, L. Soares; Tourinho Jadallah Aoude, R.] 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:000425742600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3493
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Valls, P.; Sanchez Mayordomo, C.
Title (down) Updated branching fraction measurements of B-(s)(0) -> K(S)(0)h(+)h'(-) decays Type Journal Article
Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 027 - 42pp
Keywords B physics; Branching fraction; Flavor physics; Hadron-Hadron scattering (experiments)
Abstract The charmless three-body decays B-(s)(0) -> K(S)(0)h(+)h '(-) (where h((')) – pi, K) are analysed using a sample of pp collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 3 fb(-1). The branching fractions are measured relative to that of the B-0 -> K-S(0) pi(+)pi(-) decay, and are determined to be: B(B-0 -> (KSK +/-)-K-0 pi(-/+))/B(B-0 -> K-S(0)pi(+)pi(-) = 0.123 +/- 0.009 (stat) +/- 0.015 (syst), B(B-0 -> (KSK+K-)-K-0)/B(B-0 -> K-S(0)pi(+)pi(-) = 0.549 +/- 0.018 (stat) +/- 0.033 (syst), B(B-S(0) -> K-S(0) pi(+)pi(-))/B(B-0 -> K-S(0)pi(+)pi(-)) = 0.191 +/- 0.027 (stat) +/- 0.031 (syst) +/- 0.011 (f(s)/f(d)), B(B-0 -> (KSK +/-)-K-0 pi(-/+))/B(B-0 -> K-S(0)pi(+)pi(-) = 1.70 +/- 0.07 (stat) +/- 0.11 (syst) +/- 0.10 (f(s)/f(d)), B(B-0 -> (KSK+K-)-K-0)/B(B-0 -> K-S(0)pi(+)pi(-) is an element of [0.008 – 0.051] at 90% confidence level, where f(s)/f(d) represents the ratio of hadronisation fractions of the B-s(0) and B-0 mesons.
Address [Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Molina Rodriguez, J.; dos Reis, A. C.; Rodrigues, A. B.; Salustino Guimaraes, V.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil, Email: louis.henry@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:000415206000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3364
Permanent link to this record
 
 
Author Bernabeu, J.; Martinez-Vidal, F.
Title (down) Time-Reversal Violation Type
Year 2015 Publication Annual Review of Nuclear and Particle Science Abbreviated Journal Annu. Rev. Nucl. Part. Sci.
Volume 65 Issue Pages 403-427
Keywords time reversal; CP violation; T-odd products; electric dipole moments; B mesons; K mesons; EPR entanglement
Abstract The violation of CP symmetry between matter and antimatter in the neutral K and B meson systems is well established, with a high degree of consistency between all available experimental measurements and with the Standard Model of particle physics. On the basis of the up-to-now-unbroken CPT symmetry, the violation of CP symmetry strongly suggests that the behavior of these particles under weak interactions must also be asymmetric under time reversal T. Many searches for T violation have been performed and proposed using different observables and experimental approaches. These include T-odd observables, such as triple products in weak decays, and genuine observables, such as permanent electric dipole moments of nondegenerate stationary states and the breaking of the reciprocity relation. We discuss the conceptual basis of the required exchange of initial and final states with unstable particles, using quantum entanglement and the decay as a filtering measurement, for the case of neutral B and K mesons. Using this method, the BaBar experiment at SLAC has clearly observed T violation in B mesons.
Address [Bernabeu, Jose; Martinez-Vidal, Fernando] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain
Corporate Author Thesis
Publisher Annual Reviews Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-8998 ISBN Medium
Area Expedition Conference
Notes WOS:000363473100017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2430
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title (down) Time-integrated luminosity recorded by the BABAR detector at the PEP-II e(+)e(-) collider Type Journal Article
Year 2013 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 726 Issue Pages 203-213
Keywords BABAR; Integrated luminosity; Electron-positron collider; PEP-II
Abstract We describe a measurement of the time-integrated luminosity of the data collected by the BABAR experiment at the PEP-II asymmetric-energy e(+)e(-) collider at the Upsilon(4S), Upsilon(3S), and Upsilon(2S) resonances and in a continuum region below each resonance. We measure the time-integrated luminosity by counting e(+)e(-)-> e(+)e(-) and (for the Upsilon(4S) only) e(+)e(-)->mu(+)mu(-) candidate events, allowing additional photons in the final state. We use data-corrected simulation to determine the cross-sections and reconstruction efficiencies for these processes, as well as the major backgrounds. Due to the large cross-sections of e(+)e(-)-> e(+)e(-) and e(+)e(-)->mu(+)mu(-), the statistical uncertainties of the measurement are substantially smaller than the systematic uncertainties. The dominant systematic uncertainties are due to observed differences between data and simulation, as well as uncertainties on the cross-sections. For data collected on the Upsilon(3S) and Upsilon(2S) resonances, an additional uncertainty arises due to Upsilon -> e(+)e(-)X background. For data collected off the Upsilon resonances, we estimate an additional uncertainty due to time dependent efficiency variations, which can affect the short off-resonance runs. The relative uncertainties on the luminosities of the on-resonance (off-resonance) samples are 0.43% (0.43%) for the Upsilon(4S), 0.58% (0.72%) for the Upsilon(3S), and 0.68% (0.88%) for the Upsilon(2S).
Address [Lees, J. P.; Poireau, V.; Tisserand, V.; Bettoni, D.; Bozzi, C.; Piemontese, L.; Santoro, V.; Passaggio, S.; Robutti, E.; Neri, N.; Morandin, M.; Posocco, M.; Rotondo, M.; Simi, G.; Perez, A.; Walsh, J.; Anulli, E.; Ferrarotto, F.; Gioi, L. Li; Mazzoni, M. A.; Piredda, G.] Univ Savoie, CNRS IN2P3, LAPP, F-74941 A Le Vieux, France, Email: abi@slac.stanford.edu
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000323557200028 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1561
Permanent link to this record
 
 
Author BABAR Collaboration (del Amo Sanchez, P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title (down) Time-dependent analysis of B-0 -> K-S(0)pi(-)pi(+) gamma decays and studies of the K+pi(-)pi(+) system in B+ -> K+pi(-)pi(+)gamma decays Type Journal Article
Year 2016 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 93 Issue 5 Pages 052013 - 29pp
Keywords
Abstract We measure the time-dependent CP asymmetry in the radiative-penguin decay B-0 -> K-S(0)pi(-)pi(+)gamma, using a sample of 471 x 10(6) Upsilon(4S) -> B (B) over bar events recorded with the BABAR detector at the PEP-II e(+)(e) over tilde (-) storage ring at SLAC. Using events with m(K pi pi) < 1.8 GeV/c(2), we measure the branching fractions of B+ -> K+pi(-)pi(+)gamma and B-0 -> K-S(0)pi(-)pi(+)gamma, the branching fractions of the kaonic resonances decaying to K+pi(-)pi(+)gamma, as well as the overall branching fractions of the B+ -> rho K-0(+.)gamma, B+ -> K*(0)pi(+)gamma. and S-wave B+ -> (K pi)(0)(*0) pi(+)gamma components. For events from the rho mass band, we measure the CP-violating parameters SKS0 pi+pi-gamma = 0.14 +/- 0.25 +/- 0.03 and CKS0 pi+pi-gamma = -0.39 +/- 0.20(-0.02)(+0.003), where the first uncertainties are statistical and the second are systematic. We extract from this measurement the time-dependent CP asymmetry related to the CP eigenstate rho K-0(S)0 and obtain S-KS(0) = -0.18 +/- 0.32(-0.05)(+0.06), which provides information on the photon polarization in the underlying b -> s gamma transition.
Address [Sanchez, P. del Amo; Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules LAPP, F-74941 Annecy Le Vieux, France
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:000373106200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2601
Permanent link to this record
 
 
Author Bernabeu, J.; Martinez-Vidal, F.; Villanueva-Perez, P.
Title (down) Time reversal violation from the entangled B-0(B)over-bar(0) system Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 064 - 18pp
Keywords Discrete and Finite Symmetries; B-Physics; CP violation
Abstract We discuss the concepts and methodology to implement an experiment probing directly Time Reversal (T) non-invariance, without any experimental connection to CP violation, by the exchange of in and out states. The idea relies on the B-0(B) over bar (0)) entanglement and decay time information available at B factories. The flavor or CP tag of the state of the still living neutral meson by the first decay of its orthogonal partner overcomes the problem of irreversibility for unstable systems, which prevents direct tests of T with incoherent particle states. T violation in the time evolution between the two decays means experimentally a difference between the rates for the time-ordered (l+X, J/psi K-s) and (J/psi K-L, l(-)X) decays, and three other independent asymmetries. The proposed strategy has been applied to simulated data samples of similar size and features to those currently available, from which we estimate the significance of the expected discovery to reach many standard deviations.
Address [Bernabeu, J.] Univ Valencia, Dept Theoret Phys, E-46100 Burjassot, Spain, Email: Jose.Bernabeu@uv.es;
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 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000309883600021 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1215
Permanent link to this record