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Related papers: Beyond Universality: Probing Lepton Flavor in the …

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We present constraints on Wilson coefficients from a combined fit to data from top-quark and beauty-physics measurements within the Standard Model effective field theory. We consider present data on top-quark pair production and decay,…

High Energy Physics - Phenomenology · Physics 2021-05-13 Stefan Bißmann , Cornelius Grunwald , Gudrun Hiller , Kevin Kröninger

We investigate lepton number violation (LNV) induced by $\Delta L = 2$ dimension-seven Standard Model Effective Field Theory (SMEFT) operators in the context of same-sign muon colliders. Specifically, we study $\mu^+ \mu^+ \rightarrow…

High Energy Physics - Phenomenology · Physics 2026-03-31 Subhaditya Bhattacharya , Soumyajit Datta , Abhik Sarkar

The latest measurements of rare $b\to s$ decays in the LHCb experiment have led to results in tension with the predictions of the standard model (SM), including a tentative indication of the violation of lepton flavor universality. Assuming…

High Energy Physics - Phenomenology · Physics 2015-08-31 Chao-Jung Lee , Jusak Tandean

Lepton Flavor Violating (LFV) processes are clear signals of physics beyond the Standard Model. We investigate the possibility of measuring this kind of processes at present and foreseeable future muon-electron colliders, taking into…

High Energy Physics - Phenomenology · Physics 2020-12-15 Fabio Bossi , Paolo Ciafaloni

Lepton flavor violation (LFV) offers a powerful probe of physics beyond the Standard Model, particularly in models addressing neutrino masses and the baryon asymmetry of the universe. In this study, we investigate LFV processes within the…

High Energy Physics - Phenomenology · Physics 2025-01-22 Chengcheng Han , Yijun Han , Sihui Huang , Zhanhong Lei

We calculate the one- and two-loop matching corrections in the Standard Model effective field theory (SMEFT) that impact electroweak precision measurements and flavour physics observables, focusing on the contributions of third-generation…

High Energy Physics - Phenomenology · Physics 2025-01-17 Ulrich Haisch , Luc Schnell

In recent years, evidence for lepton flavour universality violation beyond the Standard Model has been accumulated. In this context, a singly charged $SU(2)_L$ singlet scalar ($\phi^\pm$) is very interesting, as it can only have flavour…

High Energy Physics - Phenomenology · Physics 2021-05-03 Andreas Crivellin , Fiona Kirk , Claudio Andrea Manzari , Luca Panizzi

We study lepton flavour violating two- and three-body decays of pseudoscalar mesons in Effective Field Theory (EFT). We give analytic formulae for the decay rates in the presence of a complete basis of QED and QCD-invariant operators. The…

High Energy Physics - Phenomenology · Physics 2019-01-30 Sacha Davidson , Albert Saporta

We propose a novel strategy to test lepton flavor universality (LFU) in top decays, applicable to top pair production at colliders. Our proposal exploits information in kinematic distributions and mostly hinges on data-driven techniques,…

High Energy Physics - Phenomenology · Physics 2019-01-16 Jernej F. Kamenik , Andrey Katz , Daniel Stolarski

Di-Higgs couplings to fermions of the form $h^{2}\overline{f}f$ are absent in the Standard Model, however, they are present in several physics Beyond Standard Model (BSM) extensions, including those with vector-like fermions. In Effective…

High Energy Physics - Phenomenology · Physics 2024-09-25 Fayez Abu-Ajamieh , Marco Frasca , Sudhir K. Vempati

We review flavour and CP violations in the lepton sector as probes of new physics beyond the standard model and its minimal extensions accommodating massive neutrinos. After recalling the main experimental bounds and the future…

High Energy Physics - Phenomenology · Physics 2015-09-29 Ferruccio Feruglio

The $R(D^{(*)})$ puzzle stands for a $\sim3\sigma$ violation of lepton flavor universality between the decay rates of $B\to D^{(*)}\tau\nu$ and $B\to D^{(*)}\ell\nu$, where $\ell=e,\mu$. If it is accounted for by new physics, there is no…

High Energy Physics - Phenomenology · Physics 2022-08-10 Shikma Bressler , Federico De Vito Halevy , Yosef Nir

In the framework of the Standard Model Effective Field Theory, we compare the lower bounds on the scale of new physics possibly contributing to the $f\bar{f}h$ effective couplings, obtained from the measurements of different observables,…

High Energy Physics - Phenomenology · Physics 2022-05-25 J. Alonso-Gonzalez , A. de Giorgi , L. Merlo , S. Pokorski

We interpret the recent hints for lepton flavor universality violation in rare $B$ meson decays. Based on a model-independent effective Hamiltonian approach, we determine regions of new physics parameter space that give a good description…

High Energy Physics - Phenomenology · Physics 2018-05-04 Wolfgang Altmannshofer , Peter Stangl , David M. Straub

The Standard Model effective field theory (SMEFT) provides a general framework to include the dynamics of the beyond standard model physics residing at a certain higher energy scale $\Lambda$. We study the top-quark production along with a…

High Energy Physics - Phenomenology · Physics 2022-12-07 Monoranjan Guchait , Arnab Roy

This Thesis presents my personal contributions to two distinct fields, namely the recent experimental anomalies in B-meson decays, and the longstanding quest for a theoretical explanation of lepton masses and mixings, under a unifying…

High Energy Physics - Phenomenology · Physics 2021-11-02 Valerio Gherardi

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 Fermi effective theory of the weak interaction helped identify the structure of the electroweak sector of the Standard Model, and the chiral effective Lagrangian pointed towards QCD as the theory of the strong interactions. The Standard…

High Energy Physics - Phenomenology · Physics 2021-06-01 John Ellis

We analyze $K\to \pi \nu\bar \nu$ rates in a model with a TeV-scale leptoquark addressing $B$-meson anomalies, based on the flavor non-universal 4321 gauge group featuring third-generation quark-lepton unification. We show that, together…

High Energy Physics - Phenomenology · Physics 2022-10-27 Òscar L. Crosas , Gino Isidori , Javier M. Lizana , Nudzeim Selimovic , Ben A. Stefanek

Working within the context of the minimal supersymmetric standard model, we compare current bounds from quark flavor changing processes with current and upcoming bounds on lepton flavor violation. We assume supersymmetry breaking…

High Energy Physics - Phenomenology · Physics 2018-03-07 Sebastian A. R. Ellis , Aaron Pierce