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Related papers: Non-abelian gauge extensions for B-decay anomalies

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We discuss the current status of lepton flavour universality observables in semileptonic charged and neutral current $B$ meson decays. We recapitulate the current experimental situation. Assuming the current tensions with the SM are of…

High Energy Physics - Phenomenology · Physics 2020-02-05 Nejc Košnik

We present a simple $U(1)_{B_3-3L_\mu}$ gauge Standard Model extension that can easily account for the anomalies in $R(K)$ and $R(K^*)$ reported by LHCb. The model is economical in its setup and particle content. Among the Standard Model…

High Energy Physics - Phenomenology · Physics 2018-11-07 Cesar Bonilla , Tanmoy Modak , Rahul Srivastava , Jose W. F. Valle

Motivated by the recent LHCb announcement of a $3.1\sigma$ violation of lepton-flavor universality in the ratio $R_K=\Gamma(B\to K\mu^+\mu^-)/\Gamma(B\to K e^+ e^-)$, we present an updated, comprehensive analysis of the flavor anomalies…

High Energy Physics - Phenomenology · Physics 2021-09-28 Claudia Cornella , Darius A. Faroughy , Javier Fuentes-Martin , Gino Isidori , Matthias Neubert

In the Standard Model (SM), the coupling of the electroweak gauge bosons to the leptons is lepton flavour universal. Tests of this property constitute sensitive probes for new physics models that violate lepton flavour universality. Recent…

High Energy Physics - Experiment · Physics 2018-07-01 Christoph Langenbruch

Lepton Flavor Universality Violation (LFUV) in $B$ decays in both neutral $b\rightarrow s l^+ l^-$ and charged $b\rightarrow cl\bar{\nu}_{l}$ processes observed in the ratios $R_{K^{(*)}}$ and $R_{D^{(*)}}$ is investigated in the framework…

High Energy Physics - Phenomenology · Physics 2022-02-16 Soumia Lebbal , Jamal Mimouni , Noureddine Mebarki

Present measurements of b->c tau nu and b->u tau nu transitions differ from the standard model predictions of lepton flavor universality by almost 4sigma. We examine new physics interpretations of this anomaly. An effective field theory…

High Energy Physics - Phenomenology · Physics 2013-01-04 Svjetlana Fajfer , Jernej F. Kamenik , Ivan Nisandzic , Jure Zupan

We analyse the recent hints of Lepton Flavor Universality violations in semi-leptonic $B$ decays within a general EFT based on a $U(2)^n$ flavor symmetry acting on the light generations of SM fermions. We analyse in particular the…

High Energy Physics - Phenomenology · Physics 2017-08-02 Marzia Bordone , Gino Isidori , Sokratis Trifinopoulos

Recent anomalies in $B\to K^{(*)}\ell\ell$ meson decays are consistent with exchange of a heavy $Z'$ vector boson. Here we try to connect such new physics to understanding the origin of flavor, by gauging generation number. Phenomenological…

High Energy Physics - Phenomenology · Physics 2017-10-16 James M. Cline , Jorge Martin Camalich

I review the recent theoretical progress on the study of tree-level semileptonic $b\to c$ decays. After briefly reviewing the latest developments on the exclusive determinations of $|V_{cb}|$, I discuss the hints on lepton flavor…

High Energy Physics - Phenomenology · Physics 2018-08-20 Olcyr Sumensari

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

Supersymmetric B-L extension of the Standard Model (SM) is one of the best candidate for physics beyond the SM that accounts for TeV scale seesaw mechanism and provides an attractive solution for the Higgs naturalness problem. We analyze…

High Energy Physics - Phenomenology · Physics 2013-05-29 Shaaban Khalil

The evidence for Lepton Flavour Universality (LFU) violation in semileptonic $B$-decays has been rising over the past few years. Relying on generic effective field theory (EFT) results, it has been shown that models addressing the…

High Energy Physics - Phenomenology · Physics 2022-07-25 Lukas Allwicher , Nudžeim Selimović

Two topics have recently risen to prominence within the ongoing searches of beyond-Standard Model effects in $b$ and $c$ decays: observables that test lepton flavor universality (LFU) as well as lepton flavor violation (LFV). A coherent set…

High Energy Physics - Phenomenology · Physics 2023-10-10 Diego Guadagnoli , Patrick Koppenburg

Adding right-handed neutrino singlets and/or fermion triplets to the particle content of the Standard Model allows for the implementation of the seesaw mechanism to give mass to neutrinos and, simultaneously, for the construction of…

High Energy Physics - Phenomenology · Physics 2013-12-16 Luis M. Cebola , David Emmanuel-Costa , Ricardo Gonzalez Felipe

In light of recent measurements suggesting potential lepton flavor universality violations in semileptonic decays at collider experiments, this article provides a concise study of tree- and loop-level $B$-hadron semileptonic decays, $b \to…

High Energy Physics - Phenomenology · Physics 2025-02-05 Sonali Patnaik , Lopamudra Nayak , Rajeev Singh

We discuss the implications of the recently reported $R_K$ and $R_{K^*}$ anomalies, the lepton flavor non-universality in the $B\to K\ell^+\ell^-$ and $B\to K^*\ell^+\ell^-$. Using two sets of hadronic inputs of form factors, we perform a…

High Energy Physics - Phenomenology · Physics 2017-12-08 Wei Wang , Shuai Zhao

We analyze in detail the angular distributions in $\bar{B}\to D^*\ell \bar\nu$ decays, with a focus on lepton-flavour non-universality. We investigate the minimal number of angular observables that fully describes current and upcoming…

High Energy Physics - Phenomenology · Physics 2021-11-24 Christoph Bobeth , Marzia Bordone , Nico Gubernari , Martin Jung , Danny van Dyk

Rare semileptonic $b \to s \ell^+ \ell^-$ transitions provide some of the most promising frameworks to search for new physics effects. Recent analyses of these decays have indicated an anomalous behaviour in measurements of angular…

High Energy Physics - Phenomenology · Physics 2019-03-21 Andrea Mauri , Nicola Serra , Rafael Silva Coutinho

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

$U(1)^\prime$ extensions of the standard model with generation-dependent couplings to quarks and leptons are investigated as an explanation of anomalies in rare $B$-decays, with an emphasis on stability and predictivity up to the Planck…

High Energy Physics - Phenomenology · Physics 2022-02-02 Rigo Bause , Gudrun Hiller , Tim Höhne , Daniel F. Litim , Tom Steudtner