Records |
Author |
NA62 Collaboration (Cortina Gil, E. et al); Husek, T. |
Title |
Search for production of an invisible dark photon in (0) decays |
Type |
Journal Article |
Year |
2019 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
182 - 20pp |
Keywords |
Beyond Standard Model; Exotics; Fixed target experiments; Rare decay |
Abstract |
The results of a search for (0) decays to a photon and an invisible massive dark photon at the NA62 experiment at the CERN SPS are reported. From a total of 4.12 x 10(8) tagged (0) mesons, no signal is observed. Assuming a kinetic-mixing interaction, limits are set on the dark photon coupling to the ordinary photon as a function of the dark photon mass, improving on previous searches in the mass range 60-110 MeV/c(2). The present results are interpreted in terms of an upper limit of the branching ratio of the electro-weak decay 0improving the current limit by more than three orders of magnitude. |
Address |
[Gil, E. Cortina; Kleimenova, A.; Minucci, E.; Padolski, S.; Petrov, P.; Shaikhiev, A.; Volpe, R.] Catholic Univ Louvain, Louvain, Belgium, Email: tommaso.spadaro@cern.ch; |
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Springer |
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English |
Summary Language |
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Original Title |
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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:000469459200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4028 |
Permanent link to this record |
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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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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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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 |
NA48/2 Collaboration (Batley, J.R. et al); Fiorini, L. |
Title |
Measurement of the form factors of charged kaon semileptonic decays |
Type |
Journal Article |
Year |
2018 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
10 |
Issue |
10 |
Pages |
150 - 23pp |
Keywords |
Fixed target experiments; Rare decay |
Abstract |
A measurement of the form factors of charged kaon semileptonic decays is presented, based on 4.4 x 10(6)K(+/-) (0)e(e)(+/-) (Ke3 +/-) and 2.3 x 10(6)K(+/-) (0)+/- (K3 +/-) decays collected in 2004 by the NA48/2 experiment. The results are obtained with improved precision as compared to earlier measurements. The combination of measurements in the Ke3 +/- and K3 +/- modes is also presented. |
Address |
[Batley, J. R.; Kalmus, G.; Lazzeroni, C.; Munday, D. J.; Slater, M. W.; Wotton, S. A.] Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England, Email: Dmitri.Madigojine@cern.ch; |
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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:000449293400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3791 |
Permanent link to this record |
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Author |
Murgui, C.; Peñuelas, A.; Jung, M.; Pich, A. |
Title |
Global fit to b -> c tau nu transitions |
Type |
Journal Article |
Year |
2019 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
09 |
Issue |
9 |
Pages |
103 - 45pp |
Keywords |
Beyond Standard Model; Effective Field Theories |
Abstract |
We perform a general model-independent analysis of b -> c tau(nu) over bar (tau) transitions, including measurements of R-D, R-D*, their q(2) differential distributions, the recently measured longitudinal D* polarization F-L(D)*, and constraints from the B-c -> tau(nu) over bar (tau) lifetime, each of which has significant impact on the fit. A global fit to a general set of Wilson coefficients of an effective low-energy Hamiltonian is presented, the solutions of which are interpreted in terms of hypothetical new-physics mediators. From the obtained results we predict selected b -> c tau(nu) over bar (tau) observables, such as the baryonic transition Lambda(b) -> Lambda(c)tau(nu) over bar (tau), the ratio R-J/psi, the forward-backward asymmetries A(FB)(D()*()), the tau polarization asymmetries P-tau(D()*()), and the longitudinal D* polarization fraction F-L(D)*. The latter shows presently a slight tension with any new-physics model, such that an improved measurement could have an important impact. We also discuss the potential change due the very recently announced preliminary R-D(*) measurement by the Belle collaboration. |
Address |
[Murgui, Clara; Penuelas, Ana; Pich, Antonio] Univ Valencia, IFIC, Dept Fis Teor, CSIC, Apt Correus 22085, E-46071 Valencia, Spain, Email: Clara.Murgui@ific.uv.es; |
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Publisher |
Springer |
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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:000490861200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4177 |
Permanent link to this record |
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Author |
Molina, R.; Ruiz de Elvira, J. |
Title |
Light- and strange-quark mass dependence of the rho(770) meson revisited |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
11 |
Issue |
11 |
Pages |
017 - 74pp |
Keywords |
Chiral Lagrangians; Lattice QCD |
Abstract |
Recent lattice data on pi pi -scattering phase shifts in the vector-isovector channel, pseudoscalar meson masses and decay constants for strange-quark masses smaller or equal to the physical value allow us to study the strangeness dependence of these observables for the first time. We perform a global analysis on two kind of lattice trajectories depending on whether the sum of quark masses or the strange-quark mass is kept fixed to the physical point. The quark mass dependence of these observables is extracted from unitarized coupled-channel one-loop Chiral Perturbation Theory. This analysis guides new predictions on the rho (770) meson properties over trajectories where the strange-quark mass is lighter than the physical mass, as well as on the SU(3) symmetric line. As a result, the light- and strange-quark mass dependence of the rho (770) meson parameters are discussed and precise values of the Low Energy Constants present in unitarized one-loop Chiral Perturbation Theory are given. Finally, the current discrepancy between two- and three-flavor lattice results for the rho (770) meson is studied. |
Address |
[Molina, R.] Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, Inst Invest Paterna, Aptdo 22085, Valencia 46071, Spain, Email: raqumoli@ucm.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:000591048300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4615 |
Permanent link to this record |