Records |
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 |
Evidence for the two-body charmless baryonic decay B+ -> p(Lambda)over-bar |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
04 |
Issue |
4 |
Pages |
162 - 18pp |
Keywords |
B physics; Branching fraction; Flavor physics; Hadron-Hadron scattering (experiments) |
Abstract |
A search for the rare two-body charmless baryonic decay B+ -> p (Lambda) over bar is performed with pp collision data, corresponding to an integrated luminosity of 3 fb(-1), collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. An excess of B+ -> p (Lambda) over bar candidates with respect to background expectations is seen with a statistical significance of 4.1 standard deviations, and constitutes the first evidence for this decay. The branching fraction, measured using the B+ -> K-S(0)pi(+) decay for normalisation, is B(B+ -> p (Lambda) over bar) = (2.4(-0.8)(+)(+1.0) +/- 0.3) x 10(-7), where the first uncertainty is statistical and the second systematic. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Mirandal, J. M.; Gomes, A.; Massafferril, A.; Molina Rodriguezl, J.; dos Reis, A. C.; Rodrigues, A. B.; Salustino Guimaraes, V.; Lavra, I. Soares; Vieira, D.] CBPF, Rio De Janeiro, Brazil, Email: eduardo.rodrigues@cern.ch |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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English |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000401067200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3131 |
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 |
New algorithms for identifying the flavour of B-0 mesons using pions and protons |
Type |
Journal Article |
Year |
2017 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
77 |
Issue |
4 |
Pages |
238 - 15pp |
Keywords |
|
Abstract |
Two new algorithms for use in the analysis of pp collision are developed to identify the flavour of B mesons at production using pions and protons from the hadronization process. The algorithms are optimized and calibrated on data, using B-0 -> D- pi(+) decays from pp collision data collected by LIICh at centre -of -mass energies of 7 and 8 TeV. The tagging power of the new pion algorithm is 60% greater than the previously available one; the algorithm using protons to identify the flavour of a B-0 meson is the first of its kind. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: marta.calvi@mib.infn.it |
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Publisher |
Springer |
Place of Publication |
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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 |
1434-6044 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000399448700008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3120 |
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 B+ -> J/psi 3 pi(+)2 pi(-) and B+ -> psi (2S)pi(+)pi(+)pi(-) decays |
Type |
Journal Article |
Year |
2017 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
77 |
Issue |
2 |
Pages |
72 - 12pp |
Keywords |
|
Abstract |
The decays B+-> J/psi 3 pi(+)2 pi(-) and B+ -> psi(2S)pi(+)pi(+)pi(-) are observed for the first time using a data sample corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment in proton- proton collisions at the centre-of-mass energies of 7 and 8 TeV. The branching fractions relative to that of B+ -> psi(2S)K+ are measured to be B(B+-> J/psi 3 pi(+)2 pi(-))/B(B+ -> psi (2S)K+) = (1.88 +/- 0.17 +/- 0.09)x10(-2). B(B+ -> psi(2S)pi(+)pi(+)pi(-))/B(B+ -> psi (2S)K+) = (3.04 +/- 0.50 +/- 0.26)X10(-2) where the first uncertainties are statistical and the second are systematic. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil, Email: Ivan.Belyaev@itep.ru |
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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 |
1434-6044 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000394161100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2991 |
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 Annihilation Decay Mode B-0 -> K+K- |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
118 |
Issue |
8 |
Pages |
081801 - 9pp |
Keywords |
|
Abstract |
A search for the B-0 -> K+K- decay is performed using pp-collision data collected by LHCb. The data set corresponds to integrated luminosities of 1.0 and 2.0 fb(-1) at center-of-mass energies of 7 and 8 TeV, respectively. This decay is observed for the first time, with a significance of more than 5 standard deviations. The analysis also results in an improved measurement of the branching fraction for the B-s(0) -> pi(+)pi(-) decay. The measured branching fractions are B(B-0 -> K+K-) = (7.80 +/- 1.27 +/- 0.81 +/- 0.21) x 10(-8) and B(B-s(0) -> pi(+)p(-)) = (6.91 +/- 0.54 +/- 0.63 +/- 0.19 +/- 0.40) x 10(-7). The first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the B-0 -> K+pi(-) branching fraction used as a normalization. For the B-s(0) mode, the fourth accounts for the uncertainty on the ratio of the probabilities for b quarks to hadronize into B-s(0) and B-0 mesons. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] 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 |
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Expedition |
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Conference |
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Notes |
WOS:000394667300004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2965 |
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 b- Quark Production Cross Section in 7 and 13 TeV pp Collisions |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
118 |
Issue |
5 |
Pages |
052002 - 11pp |
Keywords |
|
Abstract |
Measurements of the cross section for producing b quarks in the reaction pp -> b (b) over barX are reported in 7 and 13 TeV collisions at the LHC as a function of the pseudorapidity. in the range 2 < eta < 5 covered by the acceptance of the LHCb experiment. The measurements are done using semileptonic decays of b-flavored hadrons decaying into a ground-state charmed hadron in association with a muon. The cross sections in the covered. range are 72.0 +/- 0.3 +/- 6.8 and 154.3 +/- 1.5 +/- 14.3 +/- μb for 7 and 13 TeV. The ratio is 2.14 +/- 0.02 +/- 0.13, where the quoted uncertainties are statistical and systematic, respectively. The agreement with theoretical expectation is good at 7 TeV, but differs somewhat at 13 TeV. The measured ratio of cross sections is larger at lower eta than the model prediction. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Kucewicz, W.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] 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 |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000396415600003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2970 |
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 |
Measurements of charm mixing and CP violation using D-0 -> K-+/-pi(-/+) decays |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
95 |
Issue |
5 |
Pages |
052004 - 14pp |
Keywords |
|
Abstract |
Measurements of charm mixing and CP violation parameters from the decay-time-dependent ratio of D-0 -> K+pi(-) to D-0 -> K-pi(+) decay rates and the charge-conjugate ratio are reported. The analysis uses (B) over bar -> D*(+) μX-, and charge-conjugate decays, where D *(+) -> D-0 pi(+), and D-0 -> K-+/-pi(-/+). The pp collision data are recorded by the LHCb experiment at center-of-mass energies root s = 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb(-1). The data are analyzed under three hypotheses: (i) mixing assuming CP symmetry, (ii) mixing assuming no direct CP violation in the Cabibbo-favored or doubly Cabibbo-suppressed decay amplitudes, and (iii) mixing allowing either direct CP violation and/or CP violation in the superpositions of flavor eigenstates defining the mass eigenstates. The data are also combined with those from a previous LHCb study of D-0 -> K pi decays from a disjoint set of D*(+) candidates produced directly in pp collisions. In all cases, the data are consistent with the hypothesis of CP symmetry. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Kucewicz, W.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil |
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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 |
2470-0010 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000399254800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3056 |
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 |
Search for the CP-violating strong decays eta -> pi(+)pi(-) and eta ' (958) -> pi(+)pi(-) |
Type |
Journal Article |
Year |
2017 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
764 |
Issue |
|
Pages |
233-240 |
Keywords |
|
Abstract |
A search for the CP-violating strong decays eta -> pi(+)pi(-) and eta ' (958) -> pi(+)pi(-) has been performed using approximately 2.5 x 10(7) events of each of the decays D+ -> pi(+)pi(+)pi(-) and D-s(+) -> pi(+)pi(+)pi(-), recorded by the LHCb experiment. The data set corresponds to an integrated luminosity of 3.0 fb(-1) of pp collision data recorded during LHC Run 1 and 0.3fb(-1) recorded in Run 2. No evidence is seen for D-(s)(+) -> pi(+)eta((')) with eta((')) -> pi(+)pi(-), and upper limits at 90% confidence level are set on the branching fractions, B(eta -> pi(+)pi(-)) < 1.6 x 10(-5) and B(eta' -> pi(+)pi(-)) < 1.8 x 10(-5). The limit for the eta decay is comparable with the existing one, while that for the eta' is a factor of three smaller than the previous limit. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0370-2693 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
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Conference |
|
Notes |
WOS:000390127100035 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2993 |
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 CP asymmetries in D-+/- -> eta 'pi(+/-) and D-S(+/-) -> eta 'pi(+/-) decays |
Type |
Journal Article |
Year |
2017 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
771 |
Issue |
|
Pages |
21-30 |
Keywords |
|
Abstract |
A search for CP violation in D-+/- -> eta 'pi(+/-) and D-S(+/-) -> eta 'pi(+/-) decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 3 fb(-1), recorded by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The measured CP-violating charge asymmetries are A(CP)(D-+/- -> eta 'pi(+/-)) = (-0.61 +/- 0.72 +/- 0.53 +/- 0.12)% and A(CP)(D-S(+/-) -> eta 'pi(+/-)) = (-0.82 +/- 0.36 +/- 0.22 +/- 0.27)%, where the first uncertainties are statistical, the second systematic, and the third are the uncertainties on the A(CP)(D-+/- -> K-S(0)pi(+/-)) and A(CP)(D-S(+/-) -> phi pi(+/-)) measurements used for calibration. The results represent the most precise measurements of these asymmetries to date. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Vieira, D.] CBPF, Rio De Janeiro, Brazil |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000406183300005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3259 |
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 |
Prompt and nonprompt J/psi production and nuclear modification in pPb collisions at root s(NN)=8.16 TeV |
Type |
Journal Article |
Year |
2017 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
774 |
Issue |
|
Pages |
159-178 |
Keywords |
|
Abstract |
The production of J/psi mesons is studied in proton-lead collisions at the centre-of-mass energy per nucleon pair root s(NN) = 8.16 TeV with the LHCb detector at the LHC. The double differential cross-sections of prompt and nonprompt J/psi production are measured as a function of the J/psi transverse momentum and rapidity in the nucleon-nucleon centre-of-mass frame. Forward-to-backward ratios and nuclear modification factors are determined. The results are compared with theoretical calculations based on collinear factorisation using nuclear parton distribution functions, on the colour glass condensate or on coherent energy loss models. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Salustino Guimaraes, V.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: Michael.Winn@cern.ch |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0370-2693 |
ISBN |
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Medium |
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Area |
|
Expedition |
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Conference |
|
Notes |
WOS:000414973200024 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3403 |
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 B-c(+) -> (DK+)-K-0 Decays |
Type |
Journal Article |
Year |
2017 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
118 |
Issue |
11 |
Pages |
111803 - 9pp |
Keywords |
|
Abstract |
Using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb(-1), recorded by the LHCb detector at center-of-mass energies of 7 and 8 TeV, the B-c(+) -> (DK+)-K-0 decay is observed with a statistical significance of 5.1 standard deviations. By normalizing to B-c(+) -> (D) over bar (0)pi(+) decays, a measurement of the branching fraction multiplied by the production rates for B-c(+) relative to B+ mesons in the LHCb acceptance is obtained, R-D0K = (f(c)/f(u)) x B(B-c(+) -> (DK+)-K-0) = (9.3(-2.5)(+2.8) +/- 0.6) x 10(-7), where the first uncertainty is statistical and the second is systematic. This decay is expected to proceed predominantly through weak annihilation and penguin amplitudes, and is the first B-c(+) decay of this nature to be observed. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Rodriguez, J. Molina; dos Reis, A. C.; Rodrigues, A. B.; Guimaraes, V. Salustino; Lavra, L. Soares] Ctr Brasileiro Pesquisas Fis, 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 |
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Conference |
|
Notes |
WOS:000396267100005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2963 |
Permanent link to this record |