Records |
Author |
LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P. |
Title |
Precision measurement of the B-s(0)-(B)over-bar(s)(0) oscillation frequency with the decay B-s(0) -> D-s(-)pi(+) |
Type |
Journal Article |
Year |
2013 |
Publication |
New Journal of Physics |
Abbreviated Journal |
New J. Phys. |
Volume |
15 |
Issue |
|
Pages |
053021 - 15pp |
Keywords |
|
Abstract |
A key ingredient to searches for physics beyond the Standard Model in B-s(0) mixing phenomena is the measurement of the B-s(0)-(B) over bar (0)(s) oscillation frequency, which is equivalent to the mass difference Delta m(s) of the B-s(0) mass eigenstates. Using the world's largest B-s(0) meson sample accumulated in a dataset, corresponding to an integrated luminosity of 1.0 fb(-1), collected by the LHCb experiment at the CERN LHC in 2011, a measurement of Delta m(s) is presented. A total of about 34 000 B-s(0) -> D-s(-)pi(+) signal decays are reconstructed, with an average decay time resolution of 44 fs. The oscillation frequency is measured to be Delta m(s) = 17.768 +/- 0.023 (stat) +/- 0.006 (syst) ps(-1), which is the most precise measurement to date. |
Address |
Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: wandernoth@physi.uni-heidelberg.de |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
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 |
1367-2630 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000318853200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1449 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Precision Measurement of the Mass and Lifetime of the Xi(-)(b) Baryon |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
113 |
Issue |
24 |
Pages |
242002 - 9pp |
Keywords |
|
Abstract |
We report on measurements of the mass and lifetime of the Xi(-)(b) baryon using about 1800 Xi(-)(b) decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0 fb(-1) collected by the LHCb experiment. The decays are reconstructed in the Xi(-)(b) -> Xi(0)(c)pi(-), Xi(0)(c) -> pK(-)K(-)pi(+) channel and the mass and lifetime are measured using the Lambda(0)(b) -> Lambda(+)(c)pi(-) mode as a reference. We measure M(Xi(-)(b)) – M(Lambda(0)(b)) = 178.36 +/- 0.46 +/- 0.16 MeV/c(2), (tau Xi(-)(b)/tau Lambda(0)(b)) = 1.089 +/- 0.026 +/- 0.011, where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the Xi(-)(b) mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] 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 |
|
Conference |
|
Notes |
WOS:000346387700009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2050 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Precision Measurement of the Mass and Lifetime of the Xi(0)(b) Baryon |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
113 |
Issue |
3 |
Pages |
032001 - 10pp |
Keywords |
|
Abstract |
Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb(-1) collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 Xi(0)(b) -> Xi(+)(c)pi(-), Xi(+)(c) -> pK(-)pi(+) signal decays are reconstructed. From this sample, the first measurement of the Xi(0)(b) baryon lifetime is made, relative to that of the Lambda(0)(b) baryon. The mass differences M(Xi(0)(b)) – M(Lambda(0)(b)) and M(Xi(+)(c)) – M(Lambda(+)(c)) are also measured with precision more than 4 times better than the current world averages. The resulting values are tau(Xi b0)/tau(Lambda b0) = 1.006 +/- 0.018 +/- 0.010, M(Xi(0)(b)) – M(Lambda(0)(b)) = 172.44 +/- 0.39 +/- 0.17 MeV/c(2), M(Xi(+)(c)) – M(Lambda(+)(c)) = 181.51 +/- 0.14 +/- 0.10 MeV/c(2), where the first uncertainty is statistical and the second is systematic. The relative rate of Xi(0)(b) to Lambda(0)(b) baryon production is measured to be f(Xi b0) B(Xi(0)(b) -> Xi(+)(c)pi(-)) B(Xi(+)(c) -> pK(-)pi(+))/f(Lambda b0) B(Lambda(0)(b) -> Lambda(+)(c)pi(-)) B(Lambda(+)(c) -> pK(-)pi(+)) = (1.88 +/- 0.04 +/- 0.03) x 10(-2), where the first factor is the ratio of fragmentation fractions, b -> Xi(0)(b) relative to b -> Lambda(0)(b). Relative production rates as functions of transverse momentum and pseudorapidity are also presented. |
Address |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Kucewicz, W.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] 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 |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000341260100003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1912 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P. |
Title |
Precision measurement of the ratio of the Lambda(0)(b) to (B)over-bar(0) lifetimes |
Type |
Journal Article |
Year |
2014 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
734 |
Issue |
|
Pages |
122-130 |
Keywords |
|
Abstract |
The LHCb measurement of the lifetime ratio of the Lambda(0)(b) baryon to the (B) over bar (0) meson is updated using data corresponding to an integrated luminosity of 3.0 fb(-1) collected using 7 and 8 TeV centre-of-mass energy pp collisions at the LHC. The decay modes used are Lambda(0)(b) -> J/psi pK(-) and (B) over bar (0) -> J/psi pi K-+(-), where the pi K-+(-) mass is consistent with that of the (K) over bar*(0)(892) meson. The lifetime ratio is determined with unprecedented precision to be 0.974 +/- 0.006 +/- 0.004, where the first uncertainty is statistical and the second systematic. This result is in agreement with original theoretical predictions based on the heavy quark expansion. Using the current world average of the (B) over bar (0) lifetime, the Lambda(0)(b) lifetime is found to be 1.479 +/- 0.009 +/- 0.010 ps. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; Nasteva, I.; dos Reis, A. C.; Rodrigues, A. B.] 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 |
|
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 |
|
Conference |
|
Notes |
WOS:000338943900025 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1862 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Production of associated Y and open charm hadrons in pp collisions at root s=7 and 8 TeV via double parton scattering |
Type |
Journal Article |
Year |
2016 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
07 |
Issue |
7 |
Pages |
052 - 36pp |
Keywords |
Forward physics; Hadron-Hadron scattering (experiments); Hard scattering; Heavy quark production; QCD |
Abstract |
Associated production of bottomonia and open charm hadrons in pp collisions at root s = 7 and 8 TeV is observed using data corresponding to an integrated luminosity of 3 fb(-1) accumulated with the LHCb detector. The observation of five combinations, Y(1S)D-0, Y(2S)D-0, Y(1S)D+, Y(2S)D+ and Y(1S)D (s) (+) , is reported. Production crosssections are measured for Y(1S)D-0 and Y(1S)D+ pairs in the forward region. The measured cross-sections and the differential distributions indicate the dominance of double parton scattering as the main production mechanism. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: Ivan.Belyaev@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 |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000379773300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2763 |
Permanent link to this record |
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|
Author |
LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P. |
Title |
Production of J/psi and Y mesons in pp collisions at root s=8 TeV |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
06 |
Issue |
6 |
Pages |
064 - 31pp |
Keywords |
Quarkonium; Heavy quark production; Particle and resonance production; Hadron-Hadron Scattering; Flavor physics |
Abstract |
The production of J/psi and gamma mesons in pp collisions at root s = 8 TeV is studied with the LHCb detector. The J/psi and gamma mesons are reconstructed in the mu(+)mu(-) decay mode and the signal yields are determined with a fit to the mu(+)mu(-) invariant mass distributions. The analysis is performed in the rapidity range 2.0 < y < 4.5 and transverse momentum range 0 < PT < 14 (15) GeV/c of the J/psi (gamma) mesons. The J/psi and gamma production cross-sections and the fraction of J/psi mesons from b-hadron decays are measured as a function of the meson P-T and y. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Massafferri, A.; Nasteva, I.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: Ciulia.Manca@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 |
|
Area |
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Expedition |
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Conference |
|
Notes |
WOS:000321381800010 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1536 |
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 |
[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 |
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 |
|
Expedition |
|
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); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Quantum numbers of the X(3872) state and orbital angular momentum in its rho(0)J/psi decay |
Type |
Journal Article |
Year |
2015 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
92 |
Issue |
1 |
Pages |
011102 - 9pp |
Keywords |
|
Abstract |
Angular correlations in B+ -> X(3872)K+ decays, with X(3872) -> rho(0)J/psi, rho(0) -> pi(+)pi(-) and J/psi -> pi(+)pi(-), are used to measure orbital angular momentum contributions and to determine the J(PC) value of the X(3872) meson. The data correspond to an integrated luminosity of 3.0 fb(-1) of proton- proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be J(PC) = 1(++). The X(3872) is found to decay predominantly through an S wave and an upper limit of 4% at 95% C.L. is set on the D-wave contribution. |
Address |
[Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Massafferri, A.; Rodrigues, B. Osorio; dos Reis, A. C.; Rodrigues, A. B.] 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 |
1550-7998 |
ISBN |
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Medium |
|
Area |
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Expedition |
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Conference |
|
Notes |
WOS:000358851100001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2325 |
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 |
Resonances and CP violation in B-s(0) and (B)over-bar(s)(0) -> j psi K+K- decays in the mass region above the I center dot(1020) |
Type |
Journal Article |
Year |
2017 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
08 |
Issue |
8 |
Pages |
037 - 28pp |
Keywords |
B physics; CP violation; Spectroscopy; Hadron-Hadron scattering (experiments) |
Abstract |
The decays of B (s) (0) and mesons into the J/psi K (+) K (-) final state are studied in the K (+) K (-) mass region above the I center dot(1020) meson in order to determine the resonant substructure and measure the CP-violating phase, I center dot (s) , the decay width, I“ (s) , and the width difference between light and heavy mass eigenstates, Delta I” (s) . A decay-time dependent amplitude analysis is employed. The data sample corresponds to an integrated luminosity of 3 fb(-1) produced in 7 and 8 TeV pp collisions at the LHC, collected by the LHCb experiment. The measurement determines I center dot (s) = 119 +/- 107 +/- 34 mrad. A combination with previous LHCb measurements using similar decays into the J/psi pi (+) pi (-) and J/psi I center dot(1020) final states gives I center dot (s) = 1 +/- 37 mrad, consistent with the Standard Model prediction. |
Address |
[Bediaga, I.; Miranda, J. M. De; Massafferri, A.; Molina Rodriguez, J.; Reis, A. C. dos; Rodrigues, A. B.; Salustino Guimaraes, V.; Soares Lavra, I.; Tourinho Jadallah Aoude, R.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: liming.zhang@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:000407690800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3255 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Search for B-c(+) decays to the p(p)over-bar pi(+) final state |
Type |
Journal Article |
Year |
2016 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
759 |
Issue |
|
Pages |
313-321 |
Keywords |
|
Abstract |
A search for the decays of the B-c(+) meson to p (p) over bar pi(+) is performed for the first time using a data sample corresponding to an integrated luminosity of 3.0 fb(-1) collected by the LHCb experiment in pp collisions at centre-of-mass energies of 7 and 8 TeV. No signal is found and an upper limit, at 95% confidence level, is set, f(c)/f(u) x B(B-c(+) -> p (p) over bar pi(+)) < 3.6 x 10(-8) in the kinematic region m(p<(p)over bar>) < 2.85 GeV/c(2), p(T)(B) < 20 GeV/c and 2.0 < y(B) < 4.5, where B is the branching fraction and f(c)(f(u)) is the fragmentation fraction of the b quark into a B-c+(B+) meson. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Massafferri, A.; Osorio Rodrigues, B.; dos Reis, A. C.; Rodrigues, A. B.] 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 |
|
Expedition |
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Conference |
|
Notes |
WOS:000380409200043 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2882 |
Permanent link to this record |