|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Precise measurement of the f(s)/f(d) ratio of fragmentation fractions and of B-s(0) decay branching fractions |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
104 |
Issue |
3 |
Pages |
032005 - 20pp |
|
|
Keywords ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
Abstract |
The ratio of the B-s(0) and B-0 fragmentation fractions, f(s)/f(d), in proton-proton collisions at the LHC, is obtained as a function of B-meson transverse momentum and collision center-of-mass energy from the combined analysis of different B-decay channels measured by the LHCb experiment. The results are described by a linear function of the meson transverse momentum or with a function inspired by Tsallis statistics. Precise measurements of the branching fractions of the B-s(0) -> J/psi phi and B-s(0)-> D-s(-)pi(+) decays are performed, reducing their uncertainty by about a factor of 2 with respect to previous world averages. Numerous B-s(0) decay branching fractions, measured at the LHCb experiment, are also updated using the new values of f(s)/f(d) and branching fractions of normalization channels. These results reduce a major source of systematic uncertainty in several searches for new physics performed through measurements of B-s(0) branching fractions. |
|
|
Address |
[Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
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:000686913600001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4947 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Measurement of CP asymmetry in D-0 -> KS0 KS0 decays |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
104 |
Issue |
3 |
Pages |
L031102 - 11pp |
|
|
Keywords ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
Abstract |
A measurement of the CP asymmetry in D-0 -> (KSKS0)-K-0 decays is reported, based on a data sample of proton-proton collisions collected by the LHCb experiment from 2015 to 2018, corresponding to an integrated luminosity of 6 fb(-1). The flavor of the D-0 candidate is determined using the charge of the D-*+/- meson, from which the decay is required to originate. The D-0 -> K+K- decay is used as a calibration channel. The time-integrated CP asymmetry for the D-0 -> (KSKS0)-K-0 mode is measured to be A(CP)(D-0 -> (KSKS0)-K-0) = (-3.1 +/- 1.2 +/- 0.4 +/- 0.2), where the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty on the CP asymmetry of the calibration channel. This is the most precise determination of this quantity to date. |
|
|
Address |
[Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
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:000692072800012 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4954 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
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 ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
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 ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
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); Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Precise determination of the B-s(0)-B-s(-0) oscillation frequency |
Type |
Journal Article |
|
Year |
2022 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat. Phys. |
|
|
Volume |
18 |
Issue |
|
Pages |
54-58 |
|
|
Keywords ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
Abstract |
Mesons comprising a beauty quark and strange quark can oscillate between particle (B-s(0)) and antiparticle (B-s(-0)) flavour eigenstates, with a frequency given by the mass difference between heavy and light mass eigenstates, Delta m(s). Here we present a measurement of Delta m(s) using B-s(0) -> D-s(-)pi(+) decays produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The oscillation frequency is found to be Delta m(s) = 17.7683 +/- 0.0051 +/- 0.0032 ps(-1), where the first uncertainty is statistical and the second is systematic. This measurement improves on the current Delta m(s) precision by a factor of two. We combine this result with previous LHCb measurements to determine Delta m(s) = 17.7656 +/- 0.0057 ps(-1), which is the legacy measurement of the original LHCb detector. |
|
|
Address |
[Aaij, R.; Butter, J. S.; Akiba, K. Carvalho; Sole, S. Ferreres; Gabriel, E.; Geertsema, R. E.; Greeven, L. M.; Heijhoff, K.; Hulsbergen, W.; Hynds, D.; Jans, E.; Klaver, S.; Koppenburg, P.; Kostiuk, I; Kuindersma, H. S.; Martinez, M. Lucio; Lukashenko, V; Mauri, A.; Merk, M.; Pellegrino, A.; Sanchez Gras, C.; Schubiger, M.; Snoch, A.; Tuning, N.; Usachov, A.; van Beuzekom, M.; Veronesi, M.] Nikhef Natl Inst Subatom Phys, Amsterdam, Netherlands, Email: alessandro.bertolin@pd.infn.it |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Nature Portfolio |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1745-2473 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000739810100002 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5075 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Search for time-dependent CP violation in D-0 -> K+K- and D-0 -> pi(+)pi(-) decays |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
104 |
Issue |
7 |
Pages |
072010 - 23pp |
|
|
Keywords ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
Abstract |
A search for time-dependent violation of the charge-parity symmetry in D-0 -> K+K- and D-0 -> pi(+)pi(-) decays is performed at the LHCb experiment using proton-proton collision data recorded from 2015 to 2018 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb(-1). The D-0 meson is required to originate from a D*(2010)(+) -> D-0 pi(+) decay, such that its flavor at production is identified by the charge of the accompanying pion. The slope of the time-dependent asymmetry of the decay rates of D-0 and (D) over bar (0) mesons into the final states under consideration is measured to be Delta YK+K- = (-2.3 +/- 1.5 +/- 0.3) x 10(-40), Delta Y pi(+)pi(-) = (-4.0 +/- 2.8 +/- 0.4) x 10(-4), where the first uncertainties are statistical and the second are systematic. These results are compatible with the conservation of the charge-parity symmetry at the level of 2 standard deviations and improve the precision by nearly a factor of 2. |
|
|
Address |
[Baptista Leite, J.; 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 |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
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:000753732900001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5119 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
Test of lepton universality in beauty-quark decays |
Type |
Journal Article |
|
Year |
2022 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat. Phys. |
|
|
Volume |
18 |
Issue |
3 |
Pages |
277-282 |
|
|
Keywords ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
Abstract |
The standard model of particle physics currently provides our best description of fundamental particles and their interactions. The theory predicts that the different charged leptons, the electron, muon and tau, have identical electroweak interaction strengths. Previous measurements have shown that a wide range of particle decays are consistent with this principle of lepton universality. This article presents evidence for the breaking of lepton universality in beauty-quark decays, with a significance of 3.1 standard deviations, based on proton–proton collision data collected with the LHCb detector at CERN's Large Hadron Collider. The measurements are of processes in which a beauty meson transforms into a strange meson with the emission of either an electron and a positron, or a muon and an antimuon. If confirmed by future measurements, this violation of lepton universality would imply physics beyond the standard model, such as a new fundamental interaction between quarks and leptons. |
|
|
Address |
[Aaij, R.; Butter, J. S.; Akiba, K. Carvalho; Sole, S. Ferreres; Gabriel, E.; Geertsema, R. E.; Greeven, L. M.; Heijhoff, K.; Hulsbergen, W.; Hynds, D.; Jans, E.; Ketel, T.; Klaver, S.; Koppenburg, P.; Kostiuk, I; Kuindersma, H. S.; Martinez, M. Lucio; Lukashenko, V; Mauri, A.; Merk, M.; Pellegrino, A.; Raven, G.; Gras, C. Sanchez; Schubiger, M.; Soares, M. Senghi; Snoch, A.; Tuning, N.; Usachov, A.; Van Beuzekom, M.; Veronesi, M.] Nikhef Natl Inst Subatom Phys, Amsterdam, Netherlands, Email: alessandro.bertolin@pd.infn.it |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Nature Portfolio |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1745-2473 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000769534600020 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5166 |
|
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. |
![goto web page (via DOI) doi](img/doi.gif)
|
|
Title |
J/psi photoproduction in Pb-Pb peripheral collisions at root S-NN=5 TeV |
Type |
Journal Article |
|
Year |
2022 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
|
Volume |
105 |
Issue |
3 |
Pages |
L032201 - 10pp |
|
|
Keywords ![sorted by Keywords field, descending order (down)](img/sort_desc.gif) |
|
|
|
Abstract |
The photoproduction of J/psi mesons at low transverse momentum is studied in peripheral lead-lead collisions collected by the LHCb Collaboration at a center-of-mass energy per nucleon pair of 5 TeV, corresponding to an integrated luminosity of 210 μb(-1). The J/psi candidates are reconstructed through the prompt decay into two muons of opposite charge in the rapidity region of 2.0 < y < 4.5. The results significantly improve previous measurements and are compared to the latest theoretical prediction. |
|
|
Address |
[Leite, J. Baptista; Bediaga, I; Torres, M. Cruz; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Machado, D. Torres] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
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 |
2469-9985 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000767144000003 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
5169 |
|
Permanent link to this record |