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Related papers: Universal Constraints on Low-Energy Flavour Models

200 papers

We investigate the flavour structure of generic extensions of the SM where quark and lepton mass hierarchies and the suppression of flavour-changing transitions originate only by the normalization constants of the fermion kinetic terms. We…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sacha Davidson , Gino Isidori , Selma Uhlig

The experimental sensitivity to $\mu \to e$ conversion on nuclei is set to improve by four orders of magnitude in coming years. However, various operator coefficients add coherently in the amplitude for $\mu \to e$ conversion, weighted by…

High Energy Physics - Phenomenology · Physics 2019-01-30 Sacha Davidson , Yoshitaka Kuno , Masato Yamanaka

We compare theoretical and experimental predictions of two main classes of models addressing fermion mass hierarchies and flavour changing neutral currents (FCNC) effects in supersymmetry: Froggatt-Nielsen (FN) U(1) gauged flavour models…

High Energy Physics - Phenomenology · Physics 2010-12-09 Emilian Dudas , Gero von Gersdorff , Jeanne Parmentier , Stefan Pokorski

We perform a global analysis of the bounds from charged lepton flavour violating observables to new physics. We parametrize generic new physics through the Effective Field Theory formalism and perform global fits beyond the common…

High Energy Physics - Phenomenology · Physics 2025-10-07 Enrique Fernández-Martínez , Xabier Marcano , Daniel Naredo-Tuero

In absence of any distinct evidence of new physics phenomena at the LHC, an increasing number of experimental studies aim at probing anomalous effects with an effective field theory (EFT) that represents a comprehensive approach for…

High Energy Physics - Experiment · Physics 2019-10-11 Kirill Skovpen

Flavour Changing Neutral Current (FCNC) processes are forbidden at tree level in the Standard Model and highly suppressed at higher orders. This makes FCNC one of the key processes to search for new physics since any small deviations from…

High Energy Physics - Experiment · Physics 2019-08-14 J. P. Araque

In a previous analysis presented in hep-ph/0412166, electroweak constraints were given on arbitrary linear combinations of a set of dimension-6 operators. Flavor universality and thus U(3)^5 flavor symmetry were assumed for the operators.…

High Energy Physics - Phenomenology · Physics 2009-11-11 Zhenyu Han

Effective operators provide a model-independent description of physics beyond the stan- dard model that is particularly useful given the absence of any signs of new physics at the Large Hadron Collider (LHC). We recast previous LHC analyses…

High Energy Physics - Phenomenology · Physics 2018-06-14 Yi Cai , Michael A. Schmidt , German Valencia

Flavour-Changing-Neutral-Currents (FCNC) play an important r\^ ole in testing the Standard Model (SM) while probing the possibility of having New Physics beyond the SM. In the SM, FCNC are forbidden at three level, but arise through…

High Energy Physics - Phenomenology · Physics 2013-08-22 G. C. Branco , M. N. Rebelo

Despite the tremendous success of the Standard Model, the arguments for the necessity of an extension are compelling. An attractive option is provided by Two-Higgs-Doublet models, due to their simplicity and them being the low-energy limit…

High Energy Physics - Phenomenology · Physics 2010-12-30 Martin Jung

We use unitarity and analyticity of scattering amplitudes to constrain fermionic operators in the standard model effective field theory. For four-fermion operators at mass dimension 8, we scatter flavor superpositions in fixed standard…

High Energy Physics - Phenomenology · Physics 2021-09-02 Grant N. Remmen , Nicholas L. Rodd

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 consider Flavour Changing Neutral Current processes in the framework of the supersymmetric extension of the Standard Model. FCNC constraints on the structure of sfermion mass matrices are reviewed. Furthermore, we analyze supersymmetric…

High Energy Physics - Phenomenology · Physics 2016-11-03 Mikolaj Misiak , Stefan Pokorski , Janusz Rosiek

We present a comprehensive, model-independent analysis of rare flavour-changing neutral current (FCNC) interactions of the top quark within an effective field theory framework. Beginning with a general parametrisation of top-FCNC couplings,…

High Energy Physics - Phenomenology · Physics 2026-02-12 Subhajit Kala , Soumitra Nandi

In this thesis we discuss the combined effects of strong and electroweak FCNC effective operators in top quark physics at the CERN LHC and lepton flavour violation at the ILC with dimension six effective operators.

High Energy Physics - Phenomenology · Physics 2008-11-21 Renato Batista Guedes

Motivated by the recent strong experimental evidence of large \nu_mu-\nu_tau neutrino mixing, we explore current bounds on the analogous mixing in the charged lepton sector. We present a general formalism for dimension-6 fermionic effective…

High Energy Physics - Phenomenology · Physics 2008-11-26 Deirdre Black , Tao Han , Hong-Jian He , Marc Sher

Flavour Changing Neutral Current (FCNC) decays are forbidden at lowest perturbative order in the Standard Model (SM) and only allowed via quantum loops. These transitions are therefore heavily suppressed in the SM, and New Physics (NP) can…

High Energy Physics - Experiment · Physics 2026-05-19 Christoph Langenbruch

Several experiments search for \mu - e flavour change, for instance in \mu ->e conversion, \mu-> e \gamma, and \mu -> 3e. This paper studies how to translate these experimental constraints from low energy to a New Physics scale M >> mW. A…

High Energy Physics - Phenomenology · Physics 2016-07-20 Sacha Davidson

Many extensions of the Standard Model(SM) generate contributions to Flavor Changing Neutral Current(FCNC) processes that must have sufficient flavor suppression to be consistent with experiments, if the new physics (NP) is associated with a…

High Energy Physics - Phenomenology · Physics 2008-12-18 Alakabha Datta

In this review article, we highlight the impact of models incorporating flavour symmetries on charged lepton flavour violating (LFV) processes. Flavour symmetries provide a natural approach to explain the peculiar mass hierarchies and…

High Energy Physics - Phenomenology · Physics 2015-06-05 Frank F. Deppisch
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