|
Records |
Links |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Measurement of the mass and production rate of Xi(-)(b)( )baryons |
Type |
Journal Article |
|
Year |
2019 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
99 |
Issue |
5 |
Pages |
052006 - 13pp |
|
|
Keywords |
|
|
|
Abstract |
The first measurement of the production rate of Xi(-)(b) baryons in pp collisions relative to that of Lambda(0 )(b)baryons is reported, using data samples collected by the LHCb experiment, and corresponding to integrated luminosities of 1, 2 and 1.6 fb(-1) at root s = 7, 8 and 13 TeV, respectively. In the kinematic region 2 < eta < 6 and p(T) < 20 GeV/c, we measure f(Xi b-)/f(Lambda b0) B(Xi(-)(b)-> J/psi Xi(-))/B(Lambda(0)(b)-> J/psi Lambda)= (10.8 +/- 0.9 +/- 0.8) x 10(-2) [root s = 7,8 TeV], f(Xi b-)/f(Lambda b0) B(Xi(-)(b)-> J/psi Xi(-))/B(Lambda(0)(b)-> J/psi Lambda) =(13.1 +/- 1.1 +/- 1.0) x 10(-2) [root s = 13 TeV], where and f(Xi b-) and f(Lambda)(b0) the fragmentation fractions of b quarks into Xi(-)(b) and Lambda(0)(b) baryons, respectively; B represents branching fractions; and the uncertainties are due to statistical and experimental systematic sources. The values of f(Xi b-)/f(Lambda b0) are obtained by invoking SU(3) symmetry in the Xi(-)(b)-> J/psi Xi(-) and Lambda(0)(b)-> J/psi Lambda decays. Production asymmetries between Xi(-)(b) and (Xi) over bar (+)(b) baryons are also reported. The mass of the Xi(-)(b) baryon is also measured relative to that of the Lambda(0)(b) baryon, from which it is found that m(Xi(-)(b)) = 5796.70 +/- 0.39 +/- 0.15 +/- 0.17 MeV/c(2), where the last uncertainty is due to the precision on the known Lambda(0)(b) mass. This result represents the most precise determination of the Xi(-)(b) mass. |
|
|
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.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher ![sorted by Publisher field, ascending order (up)](img/sort_asc.gif) |
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:000462907300001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
3970 |
|
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 Vidal, J.; Sanchez Mayordomo, C. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
First Measurement of Charm Production in its Fixed-Target Configuration at the LHC |
Type |
Journal Article |
|
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
|
|
Volume |
122 |
Issue |
13 |
Pages |
132002 - 12pp |
|
|
Keywords |
|
|
|
Abstract |
The first measurement of heavy-flavor production by the LHCb experiment in its fixed-target mode is presented. The production of J/psi and D-0 mesons is studied with beams of protons of different energies colliding with gaseous targets of helium and argon with nucleon-nucleon center-of-mass energies of root s(NN) = 86.6 and 110.4 GeV, respectively. The J/psi and D-0 production cross sections in pHe collisions in the rapidity range [2, 4.6] are found to be sigma(J/psi) = 652 +/- 33(stat) +/- 42(syst) nb/nucleon and sigma(D0) = 80.8 +/- 2.4(syst) +/- 6.3(syst) μb/nucleon, where the first uncertainty is statistical and the second is systematic. No evidence for a substantial intrinsic charm content of the nucleon is observed in the large Bjorken-x region. |
|
|
Address |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; Molina Rodriguez, J.; dos Reis, A. C.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher ![sorted by Publisher field, ascending order (up)](img/sort_asc.gif) |
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:000463900300006 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
3974 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
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 |
|
Thesis |
|
|
|
Publisher ![sorted by Publisher field, ascending order (up)](img/sort_asc.gif) |
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:000465181700002 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
3988 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Search for Lepton-Universality Violation in B+ -> K(+)l(+)l(-) Decays |
Type |
Journal Article |
|
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
|
|
Volume |
122 |
Issue |
19 |
Pages |
191801 - 13pp |
|
|
Keywords |
|
|
|
Abstract |
A measurement of the ratio of branching fractions of the decays B+ -> K+mu(+)mu(-) and B+ -> K(+)e(+)e(-) is presented. The proton-proton collision data used correspond to an integrated luminosity of 5.0 fb(-1) recorded with the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. For the dilepton mass-squared range 1.1 < q(2) < 6.0 GeV2/c(4) the ratio of branching fractions is measured to be R-K = 0.846(-0.054-0.014)(+0.060+0.016), where the first uncertainty is statistical and the second systematic. This is the most precise measurement of R-K to date and is compatible with the standard model at the level of 2.5 standard deviations. |
|
|
Address |
[Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher ![sorted by Publisher field, ascending order (up)](img/sort_asc.gif) |
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:000468227800003 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4014 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Observation of B-(s)(0) -> J/psi p(p)over-bar Decays and Precision Measurements of the B-(s)(0) Masses |
Type |
Journal Article |
|
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
|
|
Volume |
122 |
Issue |
19 |
Pages |
191804 - 10pp |
|
|
Keywords |
|
|
|
Abstract |
The first observation of the decays B-(s)(0) -> J/psi p (p) over bar is reported, using proton-proton collision data corresponding to an integrated luminosity of 5.2 fb(-1), collected with the LHCb detector. These decays are suppressed due to limited available phase space, as well as due to Okubo-Zweig-Iizuka or Cabibbo suppression. The measured branching fractions are beta(B-(s)(0) -> J/psi p (p) over bar). [4.51 +/- 0.40(stat)+/- 0.44(syst)] x 10(-7), BB(s)0 -> J/psi p (p) over bar) = 3.58 +/- 0.19(stat) 0.39(syst)] x 10(-6). For the B-s(0) meson, the result is much higher than the expected value of O(10(-9)). The small available phase space in these decays also allows for the most precise single measurement of both the B-0 mass as 5279.74 +/- 0.30(stat) 0.10(syst) MeV and the B-s(0) mass as 5366.85 +/- 0.19(stat) +/- 0.13(syst) MeV. |
|
|
Address |
[Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher ![sorted by Publisher field, ascending order (up)](img/sort_asc.gif) |
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:000468229900006 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4017 |
|
Permanent link to this record |