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Author (down) 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 CP violation in the B-s(0)-> phi phi decay and search for the B-0 -> phi phi decay Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 12 Issue 12 Pages 155 - 34pp
Keywords Hadron-Hadron scattering (experiments)
Abstract A measurement of the time-dependent CP-violating asymmetry in Bs0 ->phi phi = 7 TeV in 2011, 8 TeV in 2012 and 13 TeV in 2015 and 2016, a signal yield of around 9000 Bs0 ->phi phi decays is obtained. The CP-violating phase phi sss over bar is measured to be -0.073 +/- 0.115(stat) +/- 0.027(syst) rad, under the assumption it is independent of the helicity of the phi phi decay. In addition, the CP-violating phases of the transverse polarisations under the assumption of CP conservation of the longitudinal phase are measured. The helicity-independent direct CP-violation parameter is also measured, and is found to be |lambda| = 0.99 +/- 0.05(stat) +/- 0.01(syst). In addition, T-odd triple-product asymmetries are measured. The results obtained are consistent with the hypothesis of CP conservation in b over bar -> s over bar ss over bar transitions. Finally, a limit on the branching fraction of the B-0 -> phi phi decay is determined to be Bmml:mfenced close=“)” open=(B0 ->phi phi 2.7x10(-8) at 90% confidence level.
Address [Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, I] CBPF, Rio De Janeiro, Brazil, Email: emmy.gabriel@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:000504709300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4234
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Author (down) 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 Lepton-Flavor Violating Decays B+ -> K+ mu(+/-) e(-/+) Type Journal Article
Year 2019 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 123 Issue 24 Pages 241802 - 11pp
Keywords
Abstract A search for the lepton-flavor violating decays B+ -> K+ mu(+/-)e(-/+) is performed using a sample of proton-proton collision data, collected with the LHCb experiment at center-of-mass energies of 7 and 8 TeV and corresponding to an integrated luminosity of 3 fb(-1). No significant signal is observed, and upper limits on the branching fractions are set as B(B+ -> K+ mu(+/-)e(+)) < 7.0(95) x 10(-9) and B(B+ -> K+ mu(+/- )e(-)) < 6.4(8.8) x 10(-9) at 90% (95)% confidence level. The results improve the current best limits on these decays by more than one order of magnitude.
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 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:000502271300004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4235
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Author (down) 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
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Author (down) 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 A search for Xi(++)(cc) -> D(+)pK(-)pi(+) decays Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 124 - 21pp
Keywords Branching fraction; Charm physics; Hadron-Hadron scattering (experiments)
Abstract A search for the Xi(++)(cc) baryon through the Xi(++)(cc) -> D(+)pK(-)pi(+) decay is performed with a data sample corresponding to an integrated luminosity of 1.7 fb(-1) recorded by the LHCb experiment in pp collisions at a centre-of-mass energy of 13 TeV. No significant signal is observed in the mass range from the kinematic threshold of the decay to 3800 MeV/c(2). An upper limit is set on the ratio of branching fractions R = B(Xi(++)(cc) -> D(+)pK(-)pi(+))/B(Xi(++)(cc) -> A(c)(+) K- pi(+)pi(+)) with R < 1.7 (2.1) x 10(-2) at the 90% (95%) confidence level at the known mass of the Xi(++)(cc) state.
Address [Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, l.; Jadallah Aoude, R. Tourinho] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: alberto.correa.dos.reis@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:000509341600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4290
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Author (down) Lewandowski, L.; Reiter, P.; Birkenbach, B.; Bruyneel, B.; Clemente, E.; Eberth, J.; Hess, H.; Michelagnoli, C.; Li, H.; Perez-Vidal, R.M.; Zielinska, M.
Title Pulse-Shape Analysis and position resolution in highly segmented HPGe AGATA detectors Type Journal Article
Year 2019 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 55 Issue 5 Pages 81 - 13pp
Keywords
Abstract The performance of the Pulse-Shape Analysis (PSA) in AGATA HPGe detectors was investigated and improved employing a -ray source measurement based on e+e- annihilation radiation after decays of Na-22 by + decay. The first interaction positions of the two 511keV rays were determined and the connecting line of these two positions was compared to the known source position as a measure for the PSA performance. The position resolution and its dependence on the PSA parameters were investigated by varying most relevant input quantities: the charge carrier mobility of the holes, the response of the employed measuring electronics especially the preamplifier rise time. The relative statistical weight of charge signals and transient signals was scrutinized. The optimal distance metric of the grid-search algorithm and its impact on the position resolution were determined.
Address [Lewandowski, L.; Reiter, P.; Birkenbach, B.; Bruyneel, B.; Eberth, J.; Hess, H.] Univ Cologne, Inst Kernphys, Zulpicher Str 77, D-50937 Cologne, Germany, Email: preiter@ikp.uni-koeln.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 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000468893200002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4023
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