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Related papers: Flavour anomalies: a review

200 papers

We observe that the flavour symmetries of the Standard Model gauge sector, broken as they are in the Standard Model Yukawa Lagrangian, naturally suppress baryon and lepton number violation at low energies and, simultaneously, make it…

High Energy Physics - Phenomenology · Physics 2013-05-16 Gauthier Durieux

Recent anomalies in the decays of $B$ mesons and the Higgs boson provide hints towards lepton flavor (universality) violating physics beyond the Standard Model. We observe that four-fermion operators which can explain the $B$-physics…

High Energy Physics - Phenomenology · Physics 2016-05-13 Andreas Crivellin , Giancarlo D'Ambrosio , Martin Hoferichter , Lewis C. Tunstall

In supersymmetric extensions of the Standard Model, the lepton flavour violation (LFV) is closely related to the structure of slepton masses and mixing. Allowing for the most general flavour structure of the slepton sector, consistent with…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jan Kalinowski

The Standard Model (SM) is lepton flavor universal, and the recent measurements of lepton flavor universality in $B \to (K,K^*)\ell^{+}\ell^{-}$, for $\ell = \mu, \; e$, decays now lie close to the SM predictions. However, this is not the…

High Energy Physics - Phenomenology · Physics 2026-03-13 Ishtiaq Ahmed , Saba Shafaq , M. Jamil Aslam , Saadi Ishaq

The Littlest Higgs model with T-parity (LHT) contains new sources of flavour and CP violation both in the quark and the lepton sector. They originate from the interactions of ordinary fermions with mirror fermions mediated by new gauge…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras , Cecilia Tarantino

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

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

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

We review the sources and phenomenology of non-minimal flavour violation in the MSSM. We discuss in some detail the most important theoretical and experimental constraints, as well as promising observables to look for supersymmetric effects…

High Energy Physics - Phenomenology · Physics 2009-02-18 Sebastian Jager

The kaon sector is characterised by several processes which are under active investigation across different experiments. In this work, we present the global picture that emerges from a study of the different decay modes. We begin by…

High Energy Physics - Phenomenology · Physics 2022-09-27 G. D'Ambrosio , A. M. Iyer , F. Mahmoudi , S. Neshatpour

In spite of the large lepton flavour violation (LFV) observed in neutrino oscillations, within the Standard Model, we do \textit{not} expect any visible LFV in the charged lepton sector ($\mu \to e, \gamma$, $\tau \to \mu, \gamma$, etc.).…

High Energy Physics - Phenomenology · Physics 2008-11-26 Antonio Masiero , Sudhir K. Vempati , Oscar Vives

Since 2013, the LHCb collaboration has reported on the measurement of several observables associated to $b \to s$ transitions, finding various deviations from their predicted values in the Standard Model. These include a set of deviations…

High Energy Physics - Phenomenology · Physics 2018-10-11 Avelino Vicente

The LHCb measurements of certain ratios of decay modes testing lepton flavour non-universality might open an exciting world of new physics beyond the standard model. The latest LHCb measurements of R_K* offer some new insight beyond the…

High Energy Physics - Phenomenology · Physics 2017-11-29 T. Hurth , F. Mahmoudi , D. Martinez Santos , S. Neshatpour

Despite strong experimental evidences for their conservation at low energies, the baryon $B$ and lepton $L$ numbers are not expected to be absolute symmetries. Already violated in the Standard Model (SM) by non-perturbative effects (tiny at…

High Energy Physics - Phenomenology · Physics 2013-09-18 Gauthier Durieux

We study the extension of the Minimal Flavour Violation (MFV) hypothesis to the MSSM without R-parity. The novelty of our approach lies in the observation that supersymmetry enhances the global symmetry of the kinetic term and in the fact…

High Energy Physics - Phenomenology · Physics 2015-06-03 Giorgio Arcadi , Luca Di Luzio , Marco Nardecchia

We address the recent anomalies in semi-leptonic $B$-meson decays using a model of fermion masses based on the $U(2)$ flavor symmetry. The new contributions to $b \to s \ell \ell$ transitions arise due to a tree-level exchange of a…

High Energy Physics - Phenomenology · Physics 2016-01-20 Adam Falkowski , Marco Nardecchia , Robert Ziegler

Flavour physics represents one of the most interesting and, at the same time, less understood sector of the Standard Theory. On the one hand, the peculiar pattern of quark and lepton masses, and their mixing angles, may be the clue to some…

High Energy Physics - Phenomenology · Physics 2016-10-12 Gino Isidori

In light of the recent $R_{K^{(*)}}$ data on neutral current flavour anomalies in $B \to K^{(*)} \ell^+ \ell^-$ decays, we re-examine their quantitative interpretation in terms of an extended 331 gauge theory framework. We achieve this by…

High Energy Physics - Phenomenology · Physics 2022-08-29 Andrea Addazi , Giulia Ricciardi , Simone Scarlatella , Rahul Srivastava , José W. F. Valle

Extant anomalies in several semileptonic $B$-meson decays argue for physics beyond the Standard Model. Measurements of both neutral-current decays (such as $R_K$, $R_{K^*}$ and $B_s\rightarrow \phi\mu\mu$) as well as charged-current ones-…

High Energy Physics - Phenomenology · Physics 2019-10-23 Debajyoti Choudhury , Nilanjana Kumar , Anirban Kundu

In this letter we propose a strategy for discerning if new physics in the Wilson coefficient ${\cal C}_{9\mu}$ is dominantly lepton flavour universality violating or if it contains a sizable lepton flavour universal component (${\cal…

High Energy Physics - Phenomenology · Physics 2022-07-15 Marcel Algueró , Bernat Capdevila , Andreas Crivellin , Joaquim Matias