|
Records |
Links |
|
Author |
LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. |
|
|
Title |
Search for long-lived particles decaying to e(+/-)mu(-/+)nu |
Type |
Journal Article |
|
Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
|
|
Volume |
81 |
Issue |
3 |
Pages |
261 - 16pp |
|
|
Keywords |
|
|
|
Abstract |
Long-lived particles decaying to e(+/-) mu(-/+)nu, with masses between 7 and 50 GeV/c(2) and lifetimes between 2 and 50 ps, are searched for by looking at displaced vertices containing electrons and muons of opposite charges. The search is performed using 5.4 fb(-1) of pp collisions collected with the LHCb detector at a centre-of-mass energy of root s = 13 TeV. Three mechanisms of production of long-lived particles are considered: the direct pair production from quark interactions, the pair production from the decay of a Standard-Model-like Higgs boson with a mass of 125 GeV/c(2), and the charged current production from an on-shell W boson with an additional lepton. No evidence of these long-lived states is obtained and upper limits on the production cross-section times branching fraction are set on the different production modes. |
|
|
Address |
[Amato, S.; De Paula, L.; Rodrigues, F. Ferreira; Gandelman, M.; Hicheur, A.; Lopes, J. H.; Garcia, L. Meyer; Nasteva, I; Goicochea, J. M. Otalora; Polycarpo, E.; Rangel, M. S.; De Almeida, F. L. Souza; De Paula, B. Souza] Univ Fed Rio de Janeiro UFRJ, Rio De Janeiro, Brazil, Email: matthieu.marinangeli@gmail.com |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000634800600002 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4771 |
|
Permanent link to this record |
|
|
|
|
Author |
LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. |
|
|
Title |
Measurement of the branching fraction of the B0 -> Ds+ pi- decay |
Type |
Journal Article |
|
Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
|
|
Volume |
81 |
Issue |
4 |
Pages |
314 - 15pp |
|
|
Keywords |
|
|
|
Abstract |
A branching fraction measurement of the B0 -> Ds+</mml:msubsup>pi- decay is presented using proton-proton collision data collected with the LHCb experiment, corresponding to an integrated luminosity of 5.0<mml:mspace width=“0.166667em”></mml:mspace>fb-1. The branching fraction is found to be B(B0 -> Ds+</mml:msubsup>pi-)=(19.4 +/- 1.8 +/- 1.3 +/- 1.2)x10-6, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the B0 -> D-pi+, Ds+</mml:msubsup>-> K+K-pi+ and D--> K+pi-pi- branching fractions. This is the most precise single measurement of this quantity to date. As this decay proceeds through a single amplitude involving a b -> u charged-current transition, the result provides information on non-factorisable strong interaction effects and the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element <mml:msub>Vub. Additionally, the collision energy dependence of the hadronisation-fraction ratio <mml:msub>fs/<mml:msub>fd is measured through B<overbar></mml:mover>s0 -> Ds+pi- and B0 -> D-pi <mml:mo>+ decays. |
|
|
Address |
[Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: michel.de.cian@cem.ch |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000639810800004 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4800 |
|
Permanent link to this record |
|
|
|
|
Author |
LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C. |
|
|
Title |
Observation of new excited Bs0 states |
Type |
Journal Article |
|
Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
|
|
Volume |
81 |
Issue |
7 |
Pages |
601 - 11pp |
|
|
Keywords |
|
|
|
Abstract |
A structure is observed in the B +/- K -/+ mass spectrum in a sample of proton-proton collisions at centre-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of 9 fb-1. The structure is interpreted as the result of overlapping excited Bs0</mml:msubsup> states. With high significance, a two-peak hypothesis provides a better description of the data than a single resonance. Under this hypothesis the masses and widths of the two states, assuming they decay directly to B +/- K -/+, are determined to be m1 = 6063.5 +/- 1.2 (stat) +/- 0.8 (syst) MeV
Gamma 1 = 26 +/- 4 (stat) +/- 4 (syst) MeV
m2 = 6114 +/- 3 (stat) +/- 5 (syst) MeV
Gamma 2 = 66 +/- 18 (stat) +/- 21 (syst) MeV
Alternative values assuming a decay through B +/- K -/+, with a missing photon from the B +/- -> B +/- gamma decay, which are shifted by approximately 45 MeV, are also determined. The possibility of a single state decaying in both channels is also considered. The ratio of the total production cross-section times branching fraction of the new states relative to the previously observed Bs20 state is determined to be 0.87 +/- 0.15 (stat)+/- 0.19 (syst). |
|
|
Address |
[Leite, J. Baptista; Bediaga, I.; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Kucewicz, W.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fisicas CBPF, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000691564500002 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4957 |
|
Permanent link to this record |
|
|
|
|
Author |
LHCb Collaboration (Aaij, R. et al); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. |
|
|
Title |
First measurement of the CP-violating phase in B-s(0) -> J/Psi (-> e(+) e(-))phi decays |
Type |
Journal Article |
|
Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
|
|
Volume |
81 |
Issue |
11 |
Pages |
1026 - 18pp |
|
|
Keywords |
|
|
|
Abstract |
A flavour-tagged time-dependent angular analysis of B-s(0) -> J/Psi phi decays is presented where the J/Psi meson is reconstructed through its decay to an e(+)e(-) pair. The analysis uses a sample of pp collision data recorded with the LHCb experiment at centre-of-mass energies of 7 and 8TeV, corresponding to an integrated luminosity of 3 fb(-1). The CP-violating phase and lifetime parameters of the B-s(0) s system are measured to be phi(s) = 0.00 +/- 0.28 +/- 0.07 rad, Delta Gamma(s) = 0.115 +/- 0.045 +/- 0.011 ps(-1) and Delta Gamma(s) = 0.608 +/- 0.018 +/- 0.012 ps(-1) where the first uncertainty is statistical and the second systematic. This is the first time that CP-violating parameters are measured in the B-s(0) -> J/Psi phi decay with an e+e- pair in the final state. The results are consistent with previous measurements in other channels and with the Standard Model predictions. |
|
|
Address |
[Leite, J. Baptista; Bediaga, I; CruzTorres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: varvara.batozskaya@ncbj.gov.pl; |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000722225100003 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5033 |
|
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. |
|
|
Title |
Measurement of psi (2S) production cross-sections in proton-proton collisions at v s=7 and 13 TeV |
Type |
Journal Article |
|
Year |
2020 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
|
|
Volume |
80 |
Issue |
3 |
Pages |
185 - 23pp |
|
|
Keywords |
|
|
|
Abstract |
The cross-sections of.(2S) meson production in proton-proton collisions at v s = 13 TeV are measured with a data sample collected by the LHCb detector corresponding to an integrated luminosity of 275 pb-1. The production cross-sections for prompt.(2S) mesons and those for.(2S) mesons from b-hadron decays (.(2S)-from-b) are determined as functions of the transverse momentum, pT, and the rapidity, y, of the.(2S) meson in the kinematic range 2 < pT < 20 GeV/c and 2.0 < y < 4.5. The production cross-sections integrated over this kinematic region are s(prompt.(2S), 13 TeV) = 1.430 +/- 0.005 (stat) +/- 0.099 (syst) μb, s(.(2S)-from-b, 13 TeV) = 0.426 +/- 0.002 (stat) +/- 0.030 (syst) μb. A new measurement of.(2S) production cross-sections in pp collisions at v s = 7 TeV is also performed using data collected in 2011, corresponding to an integrated luminosity of 614 pb-1. The integrated production cross-sections in the kinematic range 3.5 < pT < 14 GeV/c and 2.0 < y < 4.5 are s(prompt.(2S), 7 TeV) = 0.471 +/- 0.001 (stat) +/- 0.025 (syst) μb, s(.(2S)-from-b, 7 TeV) = 0.126 +/- 0.001 (stat) +/- 0.008 (syst) μb. All results show reasonable agreement with theoretical calculations. |
|
|
Address |
[Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Kucewicz, W.; Massafferri, A.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: prli@lzu.edu.cn; |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000518614200004 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4322 |
|
Permanent link to this record |