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Related papers: Interpreting Hints for Lepton Flavor Universality …

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At the back of succeeding measurements of anomalies in semileptonic decays at LHCb and several collider experiments hinting at the possible violation of lepton flavor universality, we undertake a concise review of theoretical foundations of…

High Energy Physics - Phenomenology · Physics 2023-03-14 Sonali Patnaik , Rajeev Singh

Recent results from the LHC's first run have revealed intriguing departures from lepton flavour universality in the semi-leptonic decays of $B$-mesons. We discuss the complementary role that rare kaon decays can provide in testing new…

High Energy Physics - Phenomenology · Physics 2017-04-05 Lewis C. Tunstall , Andreas Crivellin , Giancarlo D'Ambrosio , Martin Hoferichter

High precision electroweak tests, such as deviations from the Standard Model expectations of the Lepton Flavor Universality breaking in K->lnu (with l= e or mu), represent a powerful tool to test the Standard Model and, hence, to constrain…

High Energy Physics - Phenomenology · Physics 2009-01-06 A. Masiero , P. Paradisi , R. Petronzio

Studies of lepton-flavor violation in strangeness-changing ($|\Delta S|=1$) transitions have a~long tradition in the kaon sector where they provide some of the strongest limits on physics beyond the standard model. Recent hints of violation…

High Energy Physics - Phenomenology · Physics 2019-07-10 Xiao-Gang He , Jusak Tandean , German Valencia

LHCb has reported deviations from the Standard Model in $b\to s\mu^+\mu^-$ transitions for which a new neutral gauge boson is a prime candidate for an explanation. As this gauge boson has to couple in a flavour non-universal way to muons…

High Energy Physics - Phenomenology · Physics 2015-09-25 Andreas Crivellin , Lars Hofer , Joaquim Matias , Ulrich Nierste , Stefan Pokorski , Janusz Rosiek

An important prediction of the standard model is the universality of the gauge interactions of the three generation of charged leptons. Violation of this universality would be a clean evidence of new physics (NP) beyond the standard model.…

High Energy Physics - Phenomenology · Physics 2018-10-02 Alakabha Datta

The measurements carried out at LEP and SLC projected us into the precision era of electroweak physics. This has also been relevant in the theoretical interpretation of LHCb and Belle measurements of rare $B$ semileptonic decays, paving the…

High Energy Physics - Phenomenology · Physics 2021-02-05 Lina Alasfar , Aleksandr Azatov , Jorge de Blas , Ayan Paul , Mauro Valli

Recent anomalies in $B$-meson decays, such as deviations in $R_{D^{(*)}}$ and $B\to K\nu{\bar\nu}$, suggest possible lepton flavor universality violation and new exotic interactions. In this work, we explore these anomalies within a…

High Energy Physics - Phenomenology · Physics 2025-06-04 Bhubanjyoti Bhattacharya , Alakabha Datta , Gaber Faisel , Shaaban Khalil , Shibasis Roy

The measurements of the ratios $R_{K^{(*)}}$ along with $R_{D^{(*)}}$ hint towards lepton flavor non universality which is in disagreement with the standard model. In this work, we reanalyze the four new physics models, which are widely…

High Energy Physics - Phenomenology · Physics 2019-08-27 Ashutosh Kumar Alok , Jacky Kumar , Dinesh Kumar , Ruchi Sharma

Motivated by the recent hints of lepton flavour non-universality in $B$-meson semi-leptonic decays, we study the constraints of perturbative unitarity on the new physics interpretation of the anomalies in $b \to c \ell \bar \nu$ and $b \to…

High Energy Physics - Phenomenology · Physics 2017-10-10 Luca Di Luzio , Marco Nardecchia

We analyse the rare processes $K \to \pi\nu\bar\nu$ in view of the recent hints of violations of Lepton Flavour Universality (LFU) observed in B meson decays. If, as suggested by present data, the new interactions responsible for LFU…

High Energy Physics - Phenomenology · Physics 2017-10-25 Marzia Bordone , Dario Buttazzo , Gino Isidori , Joachim Monnard

The $B\to K^*\mu\mu$ decay exhibits deviations with respect to Standard Model expectations and the measurement of the ratio $R_K$ hints at a violation of lepton-flavour universality in $B\to K\ell\ell$ transitions. Both effects can be…

High Energy Physics - Phenomenology · Physics 2017-09-13 Bernat Capdevila , Sebastien Descotes-Genon , Joaquim Matias , Javier Virto

In view of the emerging hints for the violation of lepton flavour universality in several $B$-meson decays, we conduct a model-independent study (effective field theory approach) of several well-motivated new physics scenarios. Taking into…

High Energy Physics - Phenomenology · Physics 2021-04-02 J. Kriewald , C. Hati , J. Orloff , A. M. Teixeira

B-decays mediated by both charged currents and neutral currents have provided hints of violation of lepton flavour universality. By assuming an explanation of these anomalies in terms of new physics at the TeV scale affecting the third…

High Energy Physics - Phenomenology · Physics 2018-08-07 Ferruccio Feruglio

We study the recently found anomalies in $B$-meson decays within a scenario with a warped extra dimension where the Standard Model fermions are propagating in the bulk. The anomalies are then interpreted as the result of the exchange of…

High Energy Physics - Phenomenology · Physics 2017-09-18 Eugenio Megias , Mariano Quiros , Lindber Salas

Several experimental measurements of $B$ meson decays, in tension with Standard Model predictions, exhibit large sources of Lepton Flavour Universality violation. We perform an analysis of the effects of the global fits to the Wilson…

High Energy Physics - Phenomenology · Physics 2021-10-26 Jorge Alda , Jaume Guasch , Siannah Penaranda

In view of both the latest LHCb measurement of $R_{K^{(*)}}$ and the new $2.8\sigma$ deviation reported by Belle II on $B^{+}\to K^{+}\nu\bar{\nu}$ decays, we present a fit to the $B$ meson anomalies for various one and two dimensional…

High Energy Physics - Phenomenology · Physics 2024-02-19 Peter Athron , R. Martinez , Cristian Sierra

We confront the indications of lepton flavor universality (LFU) violation observed in semi-tauonic $B$ meson decays with new physics (NP) searches using high $p_T$ tau leptons at the LHC. Using effective field theory arguments we correlate…

High Energy Physics - Phenomenology · Physics 2016-11-15 Darius A. Faroughy , Admir Greljo , Jernej F. Kamenik

Motivated by recent experimental measurements on flavour physics, in tension with Standard Model predictions, we perform an updated analysis of New Physics violating Lepton Flavour Universality, by using the effective Lagrangian approach…

High Energy Physics - Phenomenology · Physics 2019-09-04 Jorge Alda , Jaume Guasch , Siannah Peñaranda

The concept of lepton flavour universality (LFU), according to which the three lepton families are equivalent except for their masses, is a cornerstone prediction of the Standard Model (SM). LFU can be violated in models beyond the SM by…

High Energy Physics - Experiment · Physics 2019-05-22 Elena Graverini