Records |
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 |
Model-Independent Observation of Exotic Contributions to B degrees -> J/psi K+pi(-) Decays |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
122 |
Issue |
15 |
Pages |
152002 - 10pp |
Keywords |
|
Abstract |
An angular analysis of B degrees -> J/psi K+pi(-) decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3 fb(-1) collected with the LHCb detector. The m(K+pi(-) ) spectrum is divided into fine bins. In each m(K+pi(-)) bin, the hypothesis that the three-dimensional angular distribution can be described by structures induced only by K* resonances is examined, making minimal assumptions about the K+pi(-) system. The data reject the K*-only hypothesis with a large significance, implying the observation of exotic contributions in a model-independent fashion. Inspection of the m(J/psi pi(-)) vs m(K+pi(-)) plane suggests structures near m(J/psi pi(-)) = 4200 and 4600 MeV. |
Address |
[Bediaga, I.; Torres, M. Cruz; De Miranda, J. M.; Dorigo, M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Lavra, L. Soares; Aoude, R. Tourinho Jadallah] CBPF, Rio De Janeiro, Brazil |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9007 |
ISBN |
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Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000465181700002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3988 |
Permanent link to this record |
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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 |
Strong constraints on the b -> s gamma photon polarisation from B-0 -> K(*0)e(+)e(-) decays |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
12 |
Issue |
12 |
Pages |
081 - 25pp |
Keywords |
Rare decay; Flavour Changing Neutral Currents; Polarization; B physics; Hadron-Hadron scattering (experiments) |
Abstract |
An angular analysis of the B-0 -> K*(0)e(+)e(-) decay is performed using a data sample corresponding to an integrated luminosity of 9 fb(-1) of pp collisions collected with the LHCb experiment. The analysis is conducted in the very low dielectron mass squared (q(2)) interval between 0.0008 and 0.257 GeV2, where the rate is dominated by the B-0 -> K*(0)gamma transition with a virtual photon. The fraction of longitudinal polarisation of the K*(0) meson, F-L, is measured to be F-L = (4.4 +/- 2.6 +/- 1.4)%, where the first uncertainty is statistical and the second systematic. The A(T)(Re) observable, which is related to the lepton forward-backward asymmetry, is measured to be A(T)(Re) = -0.06 +/- 0.08 +/- 0.02. The A(T)((2)) and A(T)(Im) transverse asymmetries, which are sensitive to the virtual photon polarisation, are found to be A(T)((2)) = 0.11 +/- 0.10 +/- 0.02 and A(T)(Im) = 0.02 +/- 0.10 +/- 0.01. The results are consistent with Standard Model predictions and provide the world's best constraint on the b -> s gamma photon polarisation. |
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 |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000599160700001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4642 |
Permanent link to this record |
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|
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 |
Measurement of CP-Averaged Observables in the B-0 -> K-star 0 mu(+)mu(-) Decay |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
125 |
Issue |
1 |
Pages |
011802 - 13pp |
Keywords |
|
Abstract |
An angular analysis of the B-0 -> K-0 (-> K+pi(-))mu(+)mu(-) decay is presented using a dataset corresponding to an integrated luminosity of 4.7 fb(-1) of pp collision data collected with the LHCb experiment. The full set of CP-averaged observables are determined in bins of the invariant mass squared of the dimuon system. Contamination from decays with the K+ pi(-) system in an S-wave configuration is taken into account. The tension seen between the previous LHCb results and the standard model predictions persists with the new data. The precise value of the significance of this tension depends on the choice of theory nuisance parameters. |
Address |
[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 |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
|
Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0031-9007 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000544856400004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4451 |
Permanent link to this record |
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|
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 |
Measurements of CP asymmetries in charmless four-body Lambda(0)(b) and Xi(0)(b) decays |
Type |
Journal Article |
Year |
2019 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
79 |
Issue |
9 |
Pages |
745 - 19pp |
Keywords |
|
Abstract |
Asearch for CP violation in charmless four-body decays of Lambda(0)(b) and Xi(0)(b) baryons with a proton and three charged mesons in the final state is performed. To cancel out production and detection charge-asymmetry effects, the search is carried out by measuring the difference between the CP asymmetries in a charmless decay and in a decay with an intermediate charmed baryon with the same particles in the final state. The data sample used was recorded in 2011 and 2012 with the LHCb detector and corresponds to an integrated luminosity of 3 fb(-1). A total of 18 CP asymmetries are considered, either accounting for the full phase space of the decays or exploring specific regions of the decay kinematics. No significant CP-violation effect is observed in any of the measurements. |
Address |
[Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; dos Reis, A. C.; Soares Lavra, L.] CBPF, Rio De Janeiro, Brazil |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000484910400002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4141 |
Permanent link to this record |
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|
|
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 |
Measurement of the CP Violation Parameter A(r) in D-0 -> K+K- and D-0 -> pi(+)pi(-) Decays |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
118 |
Issue |
26 |
Pages |
261803 - 9pp |
Keywords |
|
Abstract |
Asymmetries in the time-dependent rates of D-0 -> K+K- and D-0 -> pi(+)pi(-)decays are measured in a pp collision data sample collected with the LHCb detector during LHC Run 1, corresponding to an integrated luminosity of 3 fb(-1). The asymmetries in effective decay widths between D-0 and (D) over bar (0) decays, sensitive to indirect CP violation, are measured to be A(r)(K+K-) = (-0.30 +/- 0.32 0.10) x 10(-3) and A(r) pi(+)pi(-)) = (0.46 +/- 0.58 +/- 0.12) x 10(-3), where the first uncertainty is statistical and the second systematic. These measurements show no evidence for CP violation and improve on the precision of the previous best measurements by nearly a factor of two. |
Address |
[Bediaga, I.; De Miranda, J. M.; De Serio, M.; Gomes, A.; Massafferri, A.; Molina Rodriguez, J.; Palano, A.; Pappagallo, M.; Pastore, A.; dos Reis, A. C.; Rodrigues, A. B.; Soares Lavra, L.] CBPF, Rio De Janeiro, Brazil |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0031-9007 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000404345800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3187 |
Permanent link to this record |
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|
|
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 |
Bose-Einstein correlations of same-sign charged pions in the forward region in pp collisions at root s=7 TeV |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
12 |
Issue |
12 |
Pages |
025 - 22pp |
Keywords |
Hadron-Hadron scattering (experiments); Particle correlations and fluctuations; QCD |
Abstract |
Bose-Einstein correlations of same-sign charged pions, produced in proton-proton collisions at a 7TeV centre-of-mass energy, are studied using a data sample collected by the LHCb experiment. The signature for Bose-Einstein correlations is observed in the form of an enhancement of pairs of like-sign charged pions with small four-momentum difference squared. The charged-particle multiplicity dependence of the Bose-Einstein correlation parameters describing the correlation strength and the size of the emitting source is investigated, determining both the correlation radius and the chaoticity parameter. The measured correlation radius is found to increase as a function of increasing charged-particle multiplicity, while the chaoticity parameter is seen to decrease. |
Address |
[Bediagal, I.; Torres, M. Cruz; De Mirandal, J. M.; Gomes, A.; Maev, O.; Massafferri, A.; Rodriguezl, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Guimaraes, V. Salustino; Schneider, O.; Lavra, O. Soares; Aoude, R. Tourinho Jadallah] CBPF, Rio De Janeiro, Brazil, Email: Marcin.Kucharczyk@cern.ch |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1029-8479 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000417757900003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3428 |
Permanent link to this record |
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|
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 |
Observation of charmless baryonic decays B-(s)(0) -> p(p)over-barh plus h '(-) |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
96 |
Issue |
5 |
Pages |
051103 - 10pp |
Keywords |
|
Abstract |
Decays of B-0 and B-s(0) mesons to the charmless baryonic final states p (p) over barh(+)h'(-), where h and h' each denote a kaon or a pion, are searched for using the LHCb detector. The analysis is based on a sample of proton-proton collision data collected at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb(-1). Four-body charmless baryonic B-s(0) decays are observed for the first time. The decays B-s(0) -> p (p) over barK(+) K-, B-s(0) -> p (p) over barK(+/-) pi(inverted perpendicular), B-0 -> p (p) over barK(+) pi(inverted perpendicular) and B-0 -> p (p) over bar pi(+) pi(-) are observed with a significance greater than 5 standard deviations; evidence at 4.1 standard deviations is found for the B-0 -> p (p) over barK(+) K- decay and an upper limit is set on the branching fraction for B-s(0) -> p (p) over bar pi(+) pi(-). Branching fractions in the kinematic region m(p (p) over bar) < 2850 MeV/c(2) are measured relative to the B-0 -> J/psi(-> p<(p)over bar>) K* (892)(0) channel. |
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 |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
|
Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2470-0010 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000411987100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3313 |
Permanent link to this record |
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|
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 |
Measurement of the CP-violating phase phi(s) from B-s(0) -> J/psi pi(+)pi(-) decays in 13 TeV pp collisions |
Type |
Journal Article |
Year |
2019 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
797 |
Issue |
|
Pages |
134789 - 12pp |
Keywords |
|
Abstract |
Decays of B-s(0) and (B) over bar (0)(s) mesons into J/psi pi(+)pi(-) final states are studied in a data sample corresponding to 1.9 fb(-1) of integrated luminosity collected with the LHCb detector in 13 TeV pp collisions. A time-dependent amplitude analysis is used to determine the final-state resonance contributions, the CP-violating phase phi(s) = -0.057 +/- 0.060 +/- 0.011 rad, the decay-width difference between the heavier mass B-s(0) eigenstate and the B-0 meson of -0.050 +/- 0.004 +/- 0.004 ps(-1), and the CP-violating parameter vertical bar lambda vertical bar = 1.01(-0.06)(+0.08) +/- 0.03, where the first uncertainty is statistical and the second systematic. These results are combined with previous LHCb measurements in the same decay channel using 7 TeV and 8 TeV pp collisions obtaining phi(s) = 0.002 +/- 0.044 +/- 0.012 rad, and vertical bar lambda vertical bar = 0.949 +/- 0.036 +/- 0.019. |
Address |
[Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil, Email: slavomira.stefkova@desy.de |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0370-2693 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000488071200014 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4157 |
Permanent link to this record |
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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 |
Observation of the Decay Xi(-)(b) -> pK(-)K(-) |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
118 |
Issue |
7 |
Pages |
071801 - 11pp |
Keywords |
|
Abstract |
Decays of the Xi(-)(b) and Omega(-)(b) baryons to the charmless final states ph(-)h'(-), where h((')) denotes a kaon or pion, are searched for with the LHCb detector. The analysis is based on a sample of proton-proton collision data collected at center-of-mass energies root s = 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb(-1). The decay Xi(-)(b) -> pK(-)K(-) is observed with a significance of 8.7 standard deviations, and evidence at the level of 3.4 standard deviations is found for the Xi(-)(b) -> pK(-)pi(-) decay. Results are reported, relative to the B- -> K+K-K- normalization channel, for the products of branching fractions and b-hadron production fractions. The branching fractions of Xi(-)(b) -> pK(-)pi(-) and Xi(-)(b) -> p pi(-)pi(-) relative to Xi(-)(b) -> pK(-)K(-) decays are also measured. |
Address |
[Bediaga, I.; Collazuol, G.; De Miranda, J. M.; Gomes, A.; Lucchesi, D.; Massafferri, A.; Molina Rodriguez, J.; dos Reis, A. C.; Rodrigues, A. B.; Salustino Guimaraes, V.; Soares Lavra, L.] CBPF, Rio De Janeiro, Brazil |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0031-9007 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000394096000003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2966 |
Permanent link to this record |
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|
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 |
Measurement of matter-antimatter differences in beauty baryon decays |
Type |
Journal Article |
Year |
2017 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat. Phys. |
Volume |
13 |
Issue |
4 |
Pages |
391-396 |
Keywords |
|
Abstract |
Differences in the behaviour of matter and antimatter have been observed in K and B meson decays, but not yet in any baryon decay. Such differences are associated with the non-invariance of fundamental interactions under the combined chargeconjugation and parity transformations, known as CP violation. Here, using data from the LHCb experiment at the Large Hadron Collider, we search for CP-violating asymmetries in the decay angle distributions of A(b)(0) baryons decaying to p pi(-)pi(+)pi(-) and p pi-K+K- final states. These four-body hadronic decays are a promising place to search for sources of CP violation both within and beyond the standard model of particle physics. We find evidence for CP violation in A(b)(0) to p pi(-)pi(+)pi(-) decays with a statistical significance corresponding to 3.3 standard deviations including systematic uncertainties. This represents the first evidence for CP violation in the baryon sector. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1745-2473 |
ISBN |
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Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000398262900020 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3170 |
Permanent link to this record |