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 |
Search for A ' -> mu(+)mu(-) Decays |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
124 |
Issue |
4 |
Pages |
041801 - 12pp |
Keywords |
|
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. |
Address |
[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 |
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:000510176700003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4324 |
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 f(s)/f(u) Variation with Proton-Proton Collision Energy and B-Meson Kinematics |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
124 |
Issue |
12 |
Pages |
122002 - 11pp |
Keywords |
|
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. |
Address |
[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 |
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 |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4352 |
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 Xi(++)(cc) production in pp collisions at root s=13 TeV |
Type |
Journal Article |
Year |
2020 |
Publication |
Chinese Physics C |
Abbreviated Journal |
Chin. Phys. C |
Volume |
44 |
Issue |
2 |
Pages |
022001 - 11pp |
Keywords |
doubly charmed baryons; hadron production; QCD |
Abstract |
The production of Xi(++)(cc) baryons in proton-proton collisions at a centre-of-mass energy of root s = 13 Tev is measured in the transverse-momentum range 4 < p(T) < 15 GeV/c and the rapidity range 2.0 < y < 4.5. The data used in this measurement correspond to an integrated luminosity of 1.7 fb(-1), recorded by the LHCb experiment during 2016. The ratio of the Xi(++)(cc) production cross-section times the branching fraction of the Xi(++)(cc) -> Lambda K-+(c)-pi(+)pi(+) decay relative to the prompt Lambda(+)(c) production cross-section is found to be (2.22 +/- 0.27 +/- 0.29) x 10(-4), assuming the central value of the measured Xi(++)(cc) lifetime, where the first uncertainty is statistical and the second systematic. |
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, Rio De Janeiro, Brazil |
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 |
1674-1137 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000509923300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4268 |
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 B-c(-) meson production fraction and asymmetry in 7 and 13 TeV pp collisions |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
100 |
Issue |
11 |
Pages |
112006 - 17pp |
Keywords |
|
Abstract |
The production fraction of the B-c(-) meson with respect to the sum of B- and (B) over bar (0) mesons is measured in both 7 and 13 TeV center-of-mass (c.m.) energy pp collisions produced by the Large Hadron Collider (LHC), using the LHCb detector. The rate, approximately 3.7 per mine, does not change with energy, but shows a transverse momentum dependence. The B-c(-) – B-c(+) production asymmetry is also measured and is consistent with zero within the determined statistical and systematic uncertainties of a few percent. |
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 |
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 |
2470-0010 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000502788500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4225 |
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 |
(U)pdated measurement of decay-time-dependent CP asymmetries in D-0 -> K+ K- and D-0 -> pi(+)pi(-) decays |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
101 |
Issue |
1 |
Pages |
012005 - 12pp |
Keywords |
|
Abstract |
A search for decay-time-dependent charge-parity (CP) asymmetry in D-0 -> K+ K- and D-0 -> pi(+)pi(-) eff decays is performed at the LHCb experiment using proton-proton collision data recorded at a center-of-mass energy of 13 TeV, and corresponding to an integrated luminosity of 5.4 fb(-1). The D-0 mesons are required to originate from semileptonic decays of b hadrons, such that the charge of the muon identifies the flavor of the neutral D meson at production. The asymmetries in the effective decay widths of D-0 and (D) over bar (0) mesons are determined to be A(Gamma)(K+ K-) = (-4.3 +/- 3.6 +/- 0.5) x 10(-4) and A(Gamma) (K+ K- ) = (2.2 +/- 7.0 +/- 0.8) x 10(-4), where the uncertainties are statistical and systematic, respectively. The results are consistent with CP symmetry and, when combined with previous LHCb results, yield A(Gamma) (K+ K-) = (-4.4 +/- 2.3 +/- 0.6) x 10(-4) and A(Gamma) (pi(+)pi(-))= (2.5 +/- 4.3 +/- 0.7) x 10(-4). |
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 |
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 |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000506845800002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4254 |
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 eta(c)(1S) production cross-section in p p collisions at root s=13TeV |
Type |
Journal Article |
Year |
2020 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
80 |
Issue |
3 |
Pages |
191 - 18pp |
Keywords |
|
Abstract |
Using a data sample corresponding to an integrated luminosity of 2.0 fb-1, collected by the LHCb experiment, the production of the.c(1S) state in proton-proton collisions at a centre-of-mass energy of v s = 13 TeVis studied in the rapidity range 2.0 < y < 4.5 and in the transverse momentum range 6.5 < pT < 14.0GeV. The cross-section for prompt production of.c(1S) mesons relative to that of the J/. meson is measured using the p p decay mode and is found to be s.c(1S)/sJ/. = 1.69 +/- 0.15 +/- 0.10 +/- 0.18. The quoted uncertainties are, in order, statistical, systematic and due to uncertainties on the branching fractions of the J/.. p p and.c. p p decays. The prompt.c(1S) production cross-section is determined to be s.c( 1S) = 1.26 +/- 0.11 +/- 0.08 +/- 0.14 μb, where the last uncertainty includes that on the J/. meson cross-section. The ratio of the branching fractions of b-hadron decays to the.c(1S) and J/. states is measured to be Bb..c X /Bb. J/. X = 0.48 +/- 0.03 +/- 0.03 +/- 0.05, where the last uncertainty is due to those on the branching fractions of the J/.. p p and.c. p p decays. The difference between the J/. and.c(1S) masses is also determined to be 113.0 +/- 0.7 +/- 0.1MeV, which is the most precise single measurement of this quantity to date. |
Address |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, L.] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: andrii.usachov@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 |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000528546600004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4398 |
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 |
Determination of quantum numbers for several excited charmed mesons observed in B- -> D*(+)pi(-) pi(-) decays |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
101 |
Issue |
3 |
Pages |
032005 - 24pp |
Keywords |
|
Abstract |
A four-body amplitude analysis of the B- -> D*(+)pi(-) pi(-) decay is performed, where fractions and relative phases of the various resonances contributing to the decay are measured. Several quasi-model-independent analyses are performed aimed at searching for the presence of new states and establishing the quantum numbers of previously observed charmed meson resonances. In particular the resonance parameters and quantum numbers are determined for the D-1 (2420), D-1 (2430), D-0 (2550), D-1* (2600), D-2 (2740) and D-3*(2750) states. The mixing between the D-1 (2420) and D-1 (2430) resonances is studied and the mixing parameters are measured. The dataset corresponds to an integrated luminosity of 4.7 fb(-1), collected in proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV with the LHCb detector. |
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 |
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 |
|
Series Issue |
|
Edition |
|
ISSN |
2470-0010 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000514688000001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4294 |
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 |
Observation of the semileptonic decay B+-> p(p)over-bar mu(+)nu(mu) |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
03 |
Issue |
3 |
Pages |
146 - 22pp |
Keywords |
B physics; Branching fraction; Flavor physics; Hadron-Hadron scattering (experiments) |
Abstract |
The Cabibbo-suppressed semileptonic decay B+-> pp over bar mu+nu μis observed for the first time using a sample of pp collisions corresponding to an integrated luminosity of 1.0, 2.0 and 1.7 fb at centre-of-mass energies of 7, 8 and 13TeV, respectively. The differential branching fraction is measured as a function of the pp invariant mass using the decay mode B+ ! J= K+ for normalisation. The total branching fraction is measured to be B (B+ ! pp+) = (5:27+0:23 0:21 0:15) 10 where the first uncertainty is statistical, the second systematic and the third is from the uncertainty on the branching fraction of the normalisation channel. |
Address |
[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, Email: mark.smith@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 |
|
Expedition |
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Conference |
|
Notes |
WOS:000524489600002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4369 |
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 |
Precision measurement of the Xi(++)(cc) mass |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
02 |
Issue |
2 |
Pages |
049 - 18pp |
Keywords |
Charm physics; Hadron-Hadron scattering (experiments); QCD; Spectroscopy |
Abstract |
A measurement of the Xi cc++ candidates are reconstructed via the decay modes Xi cc++->?c+K-pi+pi+ and Xi cc++->Xi c+pi+. The result, 3621.55 +/- 0.23 (stat) +/- 0.30 (syst) MeV/c(2), is the most precise measurement of the Xi cc++ mass to date. |
Address |
[Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; Dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.; Torres Machado, D.] CBPF, Rio De Janeiro, Brazil, Email: haojie.ni@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:000513450500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4299 |
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 |
Isospin Amplitudes in Lambda(0)(b) -> J/psi Lambda (Sigma(0)) and Xi(0)(b)-> J/psi Xi(0) (Lambda) Decays |
Type |
Journal Article |
Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
124 |
Issue |
11 |
Pages |
111802 - 11pp |
Keywords |
|
Abstract |
Ratios of isospin amplitudes in hadron decays are a useful probe of the interplay between weak and strong interactions and allow searches for physics beyond the standard model. We present the first results on isospin amplitudes in b-baryon decays, using data corresponding to an integrated luminosity of 8.5 fb(-1), collected with the LHCb detector in pp collisions at center of mass energies of 7, 8, and 13 TeV. The isospin amplitude ratio vertical bar A(1) (Delta(0)(b) -> J/psi(Sigma(0)) /A(0) (Delta(0)(b) -> J/psi Lambda)vertical bar, where the subscript on A indicates the final-state isospin, is measured to be less than 1/21.8 at 95% confidence level. The Cabibbo suppressed Xi(0)(b) -> J/psi Lambda decay is observed for the first time, allowing for the measurement vertical bar A(0) (Xi(0)(b) -> J/psi Lambda) / A(1/2 )(Xi(0)(b) -> J/psi Xi(0))vertical bar = 0.37 +/- 0.06 +/- 0.02, where the uncertainties are statistical and systematic, respectively. |
Address |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.; Torres Machado, D.] 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 |
|
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:000519994700005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4335 |
Permanent link to this record |