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; |
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 |
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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 |
Husek, T.; Monsalvez-Pozo, K.; Portoles, J. |
Title |
Constraints on leptoquarks from lepton-flavour-violating tau-lepton processes |
Type |
Journal Article |
Year |
2022 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
04 |
Issue |
4 |
Pages |
165 - 31pp |
Keywords |
Beyond Standard Model; Effective Field Theories |
Abstract |
Leptoquarks are ubiquitous in several extensions of the Standard Model and seem to be able to accommodate the universality-violation-driven B-meson-decay anomalies and the (g-2)(mu) discrepancy interpreted as deviations from the Standard Model predictions. In addition, the search for lepton-flavour violation in the charged sector is, at present, a major research program that could also be facilitated by the dynamics generated by leptoquarks. In this article, we consider a rather wide framework of both scalar and vector leptoquarks as the generators of lepton-flavour violation in processes involving the tau lepton. We single out its couplings to leptoquarks, thus breaking universality in the lepton sector, and we integrate out leptoquarks at tree level, generating the corresponding dimension-6 operators of the Standard Model Effective Field Theory. In ref. [1] we obtained model-independent bounds on the Wilson coefficients of those operators contributing to lepton-flavour-violating hadron tau decays and l-tau conversion in nuclei, with l = e, mu. Hence, we use those results to translate the bounds into the couplings of leptoquarks to the Standard Model fermions. |
Address |
[Husek, Tomas; Monsalvez-Pozo, Kevin; Portoles, Jorge] Univ Valencia, CSIC, Inst Fis Corpuscular, Apt Correus 2085, E-46071 Valencia, Spain, Email: tomas.husek@thep.lu.se; |
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 |
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Notes |
WOS:000788594400008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5210 |
Permanent link to this record |
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Author |
NA62 Collaboration (Cortina Gil, E. et al); Husek, T. |
Title |
First search for K+ -> pi(+) nu(nu)over-bar using the decay-in-flight technique |
Type |
Journal Article |
Year |
2019 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
791 |
Issue |
|
Pages |
156-166 |
Keywords |
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Abstract |
The NA62 experiment at the CERN SPS reports the first search for K+ -> pi(+) nu(nu) over bar using the decay-in-flight technique, based on a sample of 1.21 x10(11) K+ decays collected in 2016. The single event sensitivity is 3.15 x10(-10), corresponding to 0.267 Standard Model events. One signal candidate is observed while the expected background is 0.152 events. This leads to an upper limit of 14 x10(-10) on the K+ -> pi(+) nu(nu) over bar branching ratio at 95% CL. |
Address |
[Gil, E. Cortina; Minucci, E.; Padolski, S.; Petrov, P.; Velghe, B.; Volpe, R.; Kleimenova, A.; Perrin-Terrin, M.] Catholic Univ Louvain, B-1348 Louvain La Neuve, Belgium, Email: radoslav.marchevski@cern.ch; |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0370-2693 |
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:000462321800023 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3957 |
Permanent link to this record |
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Author |
Husek, T.; Monsalvez-Pozo, K.; Portoles, J. |
Title |
Lepton-flavour violation in hadronic tau decays and mu-tau conversion in nuclei |
Type |
Journal Article |
Year |
2021 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
01 |
Issue |
1 |
Pages |
059 - 48pp |
Keywords |
Beyond Standard Model; Effective Field Theories |
Abstract |
Within the Standard Model Effective Field Theory framework, with operators up to dimension 6, we perform a model-independent analysis of the lepton-flavour-violating processes involving tau leptons. Namely, we study hadronic tau decays and l-tau conversion in nuclei, with l = e, mu. Based on available experimental limits, we establish constraints on the Wilson coefficients of the operators contributing to these processes. Our work paves the way to extract the related information from Belle II and foreseen future experiments. |
Address |
[Husek, Tomas; Monsalvez-Pozo, Kevin; Portoles, Jorge] Univ Valencia, CSIC, Inst Fis Corpuscular, Apt Correus 22085, E-46071 Valencia, Spain, Email: Tomas.Husek@ific.uv.es; |
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 |
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Notes |
WOS:000609870600002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4686 |
Permanent link to this record |
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Author |
Husek, T.; Goudzovski, E.; Icampf, K. |
Title |
Precise Determination of the Branching Ratio of the Neutral-Pion Dalitz Decay |
Type |
Journal Article |
Year |
2019 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
122 |
Issue |
2 |
Pages |
022003 - 6pp |
Keywords |
|
Abstract |
We provide a new value for the ratio R = Gamma(pi(0) -> e(+)e(-)gamma(gamma))/Gamma(pi(0) -> gamma gamma) = 11.978(6) x 10(-3), which is by 2 orders of magnitude more precise than the current Particle Data Group average. It is obtained using the complete set of the next-to-leading-order radiative corrections in the QED sector, and incorporates up-to-date values of the pi(0)-transition-form-factor slope. The ratio R translates into the branching ratios of the two main pi(0) decay modes: B(pi(0) -> gamma gamma) = 98.8131(6)% and B(pi(0) -> e(+)e(-)gamma(gamma)) = 1.1836(6)%. |
Address |
[Husek, Tomas] Univ Valencia, IFIC, CSIC, Apt Correus 22085, E-46071 Valencia, Spain, Email: thusek@ific.uv.es; |
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:000456041800006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3886 |
Permanent link to this record |