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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. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Observation of an Excited B-c(+) State |
Type |
Journal Article |
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Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
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Volume |
122 |
Issue |
23 |
Pages |
232001 - 10pp |
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Keywords |
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Abstract |
Using pp collision data corresponding to an integrated luminosity of 8.5 fb(-1) recorded by the LHCb experiment at center-of-mass energies of root s = 7, 8, and 13 TeV, the observation of an excited B-c(+) state in the B-c(+)pi(+)pi(-) invariant-mass spectrum is reported. The observed peak has a mass of 6841.2 +/- 0.6(stat) +/- 0.1(syst) +/- 0.8(B-c(+)) MeV/c(2), where the last uncertainty is due to the limited knowledge of the B-c(+) mass. It is consistent with expectations of the B-c*(2(3)S(1))(+) state reconstructed without the low-energy photon from the B-c*(1(3)S(1))(+) -> B-c(+)gamma decay following B-c*(2(3)S(1))(+) -> B-c*(1(3)S(1))(+)pi(+)pi(-). A second state is seen with a global (local) statistical significance of 2.2 sigma (3.2 sigma) and a mass of 6872.1 +/- 1.3(stat) +/- 0.1(syst) +/- 0.8(B-c(+)) MeV/c(2), and is consistent with the B-c(2(1)S(0))(+) state. These mass measurements are the most precise to date. |
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Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, I; Jadallah Aoude, R. Tourinho] CBPF, Rio De Janeiro, Brazil |
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Publisher |
Amer Physical Soc |
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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ISSN |
0031-9007 |
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Expedition |
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Conference |
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Notes |
WOS:000471988300003 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4060 |
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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. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Measurement of CP-Averaged Observables in the B-0 -> K-star 0 mu(+)mu(-) Decay |
Type |
Journal Article |
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Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
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Volume |
125 |
Issue |
1 |
Pages |
011802 - 13pp |
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Keywords |
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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. |
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Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[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 |
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Publisher |
Amer Physical Soc |
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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ISSN |
0031-9007 |
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Expedition |
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Conference |
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Notes |
WOS:000544856400004 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4451 |
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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. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Search for A ' -> mu(+)mu(-) Decays |
Type |
Journal Article |
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Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
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Volume |
124 |
Issue |
4 |
Pages |
041801 - 12pp |
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Keywords |
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Abstract |
Searches are performed for both promptlike and long-lived dark photons, A ', produced in proton-proton collisions at a center-of-mass energy of 13 TeV. These searches look for A '->mu(+)mu(-) decays using a data sample corresponding to an integrated luminosity of 5.5 fb(-1) collected with the LHCb detector. Neither search finds evidence for a signal, and 90% confidence-level exclusion limits are placed on the gamma-A ' kinetic mixing strength. The promptlike A ' search explores the mass region from near the dimuon threshold up to 70 GeV and places the most stringent constraints to date on dark photons with 214 < m(A ') less than or similar to 740 MeV and 10.6 < m(A ') less than or similar to 30 GeV. The search for long-lived A '->mu(+)mu(-) decays places world-leading constraints on low-mass dark photons with lifetimes O(1)ps. |
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Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
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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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English |
Summary Language |
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Original Title |
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Series Editor |
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Abbreviated Series Title |
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ISSN |
0031-9007 |
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Conference |
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Notes |
WOS:000510176700003 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4324 |
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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. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Measurement of CP-Violating and Mixing-Induced Observables in B-s(0) -> phi gamma Decays |
Type |
Journal Article |
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Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
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Volume |
123 |
Issue |
8 |
Pages |
081802 - 10pp |
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Keywords |
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Abstract |
A time-dependent analysis of the B-s(0) -> phi gamma decay rate is performed to determine the CP -violating observables S-phi gamma and C-phi gamma and the mixing-induced observable A(phi gamma)(Delta). The measurement is based on a sample of pp collision data recorded with the LHCb detector, corresponding to an integrated luminosity of 3 fb(-1) at center-of-mass energies of 7 and 8 TeV. The measured values are S-phi gamma = 0.43 +/- 0.30 +/- 0.11, C-phi gamma = 0.11 +/- 0.29 +/- 0.11, and A(phi gamma)(Delta) = -0.67(-0.41)(+0.37) +/- 0.17, where the first uncertainty is statistical and the second systematic. This is the first measurement of the observables S and C in radiative B-s(0) decays. The results are consistent with the standard model predictions. |
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Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.] CBPF, Rio De Janeiro, Brazil |
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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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Area |
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Expedition |
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Conference |
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Notes |
WOS:000482452700008 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4119 |
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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. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Measurement of f(s)/f(u) Variation with Proton-Proton Collision Energy and B-Meson Kinematics |
Type |
Journal Article |
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Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
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Volume |
124 |
Issue |
12 |
Pages |
122002 - 11pp |
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Keywords |
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Abstract |
The ratio of the B-s(0) and B+ fragmentation fractions f(s) and f(u) is studied with B-s(0) -> J/psi phi and B+ -> J/psi K+ decays using data collected by the LHCb experiment in proton-proton collisions at 7, 8, and 13 TeV center-of-mass energies. The analysis is performed in bins of B-meson momentum, longitudinal momentum, transverse momentum, pseudorapidity, and rapidity. The fragmentation-fraction ratio f(s)/f(u) is observed to depend on the B-meson transverse momentum with a significance of 6.0 sigma. This dependency is driven by the 13 TeV sample (8.7 sigma), while the results for the other collision energies are not significant when considered separately. Furthermore, the results show a 4.8 sigma evidence for an increase of f(s)/f(u) as a function of collision energy. |
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Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.] CBPF, Rio De Janeiro, Brazil |
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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:000522195100005 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4352 |
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Permanent link to this record |