Records |
Author |
NA62 Collaboration (Cortina Gil, E. et al); Husek, T. |
Title |
An investigation of the very rare K+ -> pi+ nu nubar decay |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
11 |
Issue |
11 |
Pages |
042 - 57pp |
Keywords |
Fixed target experiments; Flavor physics; Flavour Changing Neutral Currents; Rare decay |
Abstract |
The NA62 experiment reports an investigation of the K+-> pi+nu nu <overbar></mml:mover> mode from a sample of K+ decays collected in 2017 at the CERN SPS. The experiment has achieved a single event sensitivity of (0.389 +/- 0.024) x 10(-10), corresponding to 2.2 events assuming the Standard Model branching ratio of (8.4 +/- 1.0) x 10(-11). Two signal candidates are observed with an expected background of 1.5 events. Combined with the result of a similar analysis conducted by NA62 on a smaller data set recorded in 2016, the collaboration now reports an upper limit of 1.78 x 10(-10) for the K+-> pi+nu nu <overbar></mml:mover> branching ratio at 90% CL. This, together with the corresponding 68% CL measurement of (0.48<mml:mo>-0.48<mml:mo>+0.72) x 10(-10), are currently the most precise results worldwide, and are able to constrain some New Physics models that predict large enhancements still allowed by previous measurements. |
Address |
[Gil, E. Cortina; Kleimenova, A.; Minucci, E.; Padolski, S.; Petrov, P.; Shaikhiev, A.; Volpe, R.; Jerhot, J.; Perrin-Terrin, M.; Lurkin, N.; Parkinson, C.] Catholic Univ Louvain, B-1348 Louvain, Belgium, Email: radoslav.marchevski@cern.ch; |
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Publisher |
Springer |
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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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000593745600001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4624 |
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 |
Test of lepton universality with Lambda(0)(b) -> pK(-) l(+)l(-) |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
40 - 27pp |
Keywords |
B physics; Branching fraction; Flavour Changing Neutral Currents; Hadron; Hadron scattering (experiments); Rare decay |
Abstract |
The ratio of branching fractions of the decays -> pK(-)mu(+)mu(-),RpK-1}, is measured for the first time using proton-proton collision data corresponding to an integrated luminosity of 4.7 fb(-1) recorded with the LHCb experiment at center-of-mass energies of 7, 8 and 13 TeV. In the dilepton mass-squared range 0.1 < q(2)< 6.0 GeV2/c(4) and the pK(-) mass range m(pK(-)) < 2600 MeV/c(2), the ratio of branching fractions is measured to be RpK-1=1.17-0.16+0.18 +/- 0.0$$ {R}{pK}<^>{-1}={1.17}{-0.16}<^>{+0.18}\pm 0.07 $$\end{document}, where the first uncertainty is statistical and the second systematic. This is the first test of lepton universality with b baryons and the first observation of the decay -> pK(-)e(+)e(-). |
Address |
[Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Erri, A. Massa; Soares Lavra, L.; Torres Machado, D.] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil, Email: vitalii.lisovskyi@cern.ch |
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Publisher |
Springer |
Place of Publication |
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Language |
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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Series Volume |
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Series Issue |
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ISSN |
1029-8479 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000534629900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4415 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Angular analysis of charged and neutral B -> K mu(+) mu(-) decays |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
082 - 25pp |
Keywords |
Rare decay; B physics; Flavour Changing Neutral Currents; Flavor physics; Hadron-Hadron Scattering |
Abstract |
The angular distributions of the rare decays B+ -> K+mu(+)mu(-) and B-0 -> K-S(0)mu(+)mu(-) are studied with data corresponding to 3 fb(-1) of integrated luminosity, collected in proton-proton collisions at 7 and 8 TeV centre-of-mass energies with the LHCb detector. The angular distribution is described by two parameters, F-H and the forward-backward asymmetry of the dimuon system A(FB), which are determined in bins of the dimuon mass squared. The parameter F-H is a measure of the contribution from (pseudo)scalar and tensor amplitudes to the decay width. The measurements of A(FB) and F-H reported here are the most precise to date and are compatible with predictions from the Standard Model. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: p.owen10@imperial.ac.uk |
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Thesis |
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Publisher |
Springer |
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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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 |
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Notes |
WOS:000336733900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1809 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. |
Title |
Differential branching fractions and isospin asymmetries of B -> K ((*)) μ(+) μ(-) decays |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
06 |
Issue |
6 |
Pages |
133 - 22pp |
Keywords |
Rare decay; Branching fraction; B physics; Flavour Changing Neutral Currents; Hadron-Hadron Scattering |
Abstract |
The isospin asymmetries of B -> K μ(+) μ(-) and B -> K (*) μ(+) μ(-) decays and the partial branching fractions of the B (0) -> K (0) μ(+) μ(-), B (+) -> K (+) μ(+) μ(-) and B (+) -> K (*+) μ(+) μ(-) decays are measured as functions of the dimuon mass squared, q (2). The data used correspond to an integrated luminosity of 3 fb(-1) from proton-proton collisions collected with the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV in 2011 and 2012, respectively. The isospin asymmetries are both consistent with the Standard Model expectations. The three measured branching fractions favour lower values than their respective theoretical predictions, however they are all individually consistent with the Standard Model. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil |
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Publisher |
Springer |
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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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 |
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Notes |
WOS:000338448800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1833 |
Permanent link to this record |
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Author |
LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P. |
Title |
Differential branching fraction and angular analysis of the decay B-0 -> K*(0)mu(+)mu(-) |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
08 |
Issue |
8 |
Pages |
131 - 31pp |
Keywords |
Rare decay; Hadron-Hadron Scattering; B physics; Flavour Changing Neutral Currents; Flavor physics |
Abstract |
The angular distribution and differential branching fraction of the decay B-0 -> K*(0)mu(+)mu(-) are studied using a data sample, collected by the LHCb experiment in pp collisions at root s = 7 TeV, corresponding to an integrated luminosity of 1.0 fb(-1). Several angular observables are measured in bins of the dimuon invariant mass squared, q(2). A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q(0)(2) = 4.9 +/- 0.9 GeV2/c(4), where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions. |
Address |
[Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Massafferri, A.; Nasteva, I.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: thomas.blake@cern.ch |
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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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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 |
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Notes |
WOS:000324114000032 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1683 |
Permanent link to this record |