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Related papers: Universal Constraints on Low-Energy Flavour Models

200 papers

Extending the Standard Model with higher-dimensional operators in an effective-field-theory (EFT) approach provides a systematic framework to study new-physics (NP) effects from a bottom-up perspective, as long as the NP scale is…

High Energy Physics - Phenomenology · Physics 2020-01-29 Marzia Bordone , Oscar Catà , Thorsten Feldmann

We derive non-equilibrium quantum transport equations for flavour-mixing fermions. We develop the formalism mostly in the context of resonant leptogenesis with two mixing Majorana fermions and one lepton flavour, but our master equations…

High Energy Physics - Phenomenology · Physics 2021-10-01 Henri Jukkala , Kimmo Kainulainen , Pyry M. Rahkila

The smallness of fermion masses and mixing angles has recently been been attributed to approximate global $U(1)$ symmetries, one for each fermion type. The parameters associated with these symmetry breakings are estimated here directly from…

High Energy Physics - Phenomenology · Physics 2009-12-30 Lawrence Hall , Steven Weinberg

We introduce the idea of flavour transfer from a non-abelian horizontal $SU(2)_f$ flavour gauge group embedded in the Standard Model flavour structure. The new flavour vector bosons, in the mass range from the tens of GeV to multi-TeV do…

High Energy Physics - Phenomenology · Physics 2024-06-21 Luc Darmé , Aldo Deandrea , Farvah Mahmoudi

We consider FCNC and CP violating processes mediated by gluino exchange in generalized supersymmetric theories. We present the constraints on flavour (F) changing squark mass terms at the electroweak energy scale, focusing our analysis on…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Gabrielli , A. Masiero , L. Silvestrini

We investigate the flavour changing neutral currents (FCNC) generated by dimension six four-fermion operators at the Large Hadron-Electron Collider (LHeC) proposed at CERN in an effective approach. This is performed by monte carlo analysis…

High Energy Physics - Phenomenology · Physics 2019-08-09 Wei Liu , Hao Sun

In supersymmetric grand-unified models, the lepton mixing matrix can possibly affect flavor-changing transitions in the quark sector. We present a detailed analysis of a model proposed by Chang, Masiero and Murayama, in which the…

High Energy Physics - Phenomenology · Physics 2015-05-27 Jennifer Girrbach , Sebastian Jager , Markus Knopf , Waldemar Martens , Ulrich Nierste , Christian Scherrer , Soren Wiesenfeldt

Flavor changing neutral current $|\Delta B|=|\Delta S|=1$ processes are sensitive to possible new physics at the electroweak scale and beyond, providing detailed information about flavor, chirality and Lorentz structure. Recently the LHCb…

High Energy Physics - Phenomenology · Physics 2014-09-24 Gudrun Hiller , Martin Schmaltz

It is presented an analysis on lepton flavour violating transitions, leptonic magnetic dipole moments and electric dipole moments in a class of models characterized by the flavour symmetry A4 x Z3 x U(1)_FN, whose choice is motivated by the…

High Energy Physics - Phenomenology · Physics 2009-07-22 Luca Merlo

A bottom-up approach has been adopted to identify a flavour model that agrees with present experimental measurements. The charged fermion mass hierarchies suggest that only the top Yukawa term should be present at the renormalisable level.…

High Energy Physics - Phenomenology · Physics 2020-09-22 Luca Merlo

We study current experimental bounds on charged lepton flavor violating (CLFV) $\mu$-$e$ interactions in the model-independent framework of the Standard Model Effective Field Theory (SMEFT). Assuming a generic flavor structure in the quark…

High Energy Physics - Phenomenology · Physics 2025-12-03 Filippo Delzanno , Kaori Fuyuto , Sergi Gonzàlez-Solís , Emanuele Mereghetti

A bottom-up approach has been adopted to identify a flavour model that agrees with present experimental measurements. The charged fermion mass hierarchies suggest that only the top Yukawa term should be present at the renormalisable level.…

High Energy Physics - Phenomenology · Physics 2022-09-21 L. Merlo

We consider the Two Higgs Doublet Model (2HDM) of type III which leads to Flavour Changing Neutral Currents (FCNC) at tree level in the leptonic sector. In the framework of this model we can have, in principle, two situations: the case (a)…

High Energy Physics - Phenomenology · Physics 2014-11-17 R. Diaz , R. Martinez , J. -Alexis Rodriguez

A bottom-up approach has been adopted to identify a flavour model that agrees with present experimental measurements. The charged fermion mass hierarchies suggest that only the top Yukawa term should be present at the renormalisable level.…

High Energy Physics - Phenomenology · Physics 2020-10-28 F. Arias-Aragon , C. Bouthelier-Madre , J. M. Cano , L. Merlo

We construct two concrete examples of flavour non-universal gauge theories which, after the inclusion of all $d\leq 4$ gauge invariant operators, allow to describe the observed pattern of flavour in the charged fermion sector without any…

High Energy Physics - Phenomenology · Physics 2023-12-22 Riccardo Barbieri , Gino Isidori

In the absence of a fundamental principle preventing charged lepton flavour violation, one expects that extensions of the Standard Model accommodating neutrino masses and mixings should also allow for charged lepton flavour violating…

High Energy Physics - Phenomenology · Physics 2015-06-03 A. Abada

Flavour physics has a long tradition of paving the way for direct discoveries of new particles and interactions. Results over the last decade have placed stringent bounds on the parameter space of physics beyond the Standard Model. Early…

High Energy Physics - Experiment · Physics 2015-06-04 Marco Gersabeck , Vladimir V. Gligorov , Nicola Serra

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

The non-unitarity of the effective leptonic mixing matrix at low energies is a generic signal of extensions of the Standard Model (SM) with extra fermionic singlet particles, i.e. sterile or right-handed neutrinos, to account for the…

High Energy Physics - Phenomenology · Physics 2015-06-22 Stefan Antusch , Oliver Fischer

Lepton flavor-violating processes offer interesting possibilities to probe new physics at multi-TeV scale. We discuss those in the framework of effective field theory, emphasizing the role of gluonic operators. Those operators are obtained…

High Energy Physics - Phenomenology · Physics 2017-08-09 Alexey A. Petrov , Dmitry V. Zhuridov