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Related papers: Flavour symmetries in the SMEFT

200 papers

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

We systematically investigate the possible phenomenological impact of residual flavour groups in the charged lepton sector. We consider all possible flavour charge assignments for abelian residual symmetries up to Z8. The allowed flavour…

High Energy Physics - Phenomenology · Physics 2025-09-24 Lorenzo Calibbi , Claudia Hagedorn , Michael A. Schmidt , James Vandeleur

Within supersymmetric SU(5) Grand Unified Theory, we present several new scenarios with anomaly free flavor symmetry U(1)_F. Within each scenario, a variety of cases offer many possibilities for phenomenologically interesting model…

High Energy Physics - Phenomenology · Physics 2011-12-22 Zurab Tavartkiladze

We show how a specific sequential breaking pattern of a U(2) flavour symmetry occurs automatically in a broad framework. The relative orientation in U(2) space of the spurion fields that breaks the U(2) symmetry is uniquely fixed, thus…

High Energy Physics - Phenomenology · Physics 2009-10-31 Riccardo Barbieri , Leonardo Giusti , Lawrence J. Hall , Andrea Romanino

A powerful aspect of effective field theories is connecting scales through renormalisation group (RG) flow. The anomalous dimension matrix of the Standard Model Effective Field Theory (SMEFT) encodes clues to where to find relics of heavy…

High Energy Physics - Phenomenology · Physics 2023-03-30 Camila S. Machado , Sophie Renner , Dave Sutherland

The idea of unification attempts to explain the structure of the Standard Model (SM) in terms of fewer fundamental forces and/or matter fields. However, traditional grand unified theories based on $SU(5)$ and $\mathrm{Spin}(10)$ shed no…

High Energy Physics - Phenomenology · Physics 2022-06-10 Joe Davighi

We study the modular symmetric standard-model effective field theory. We employ the stringy Ansatz on coupling structure that 4-point couplings $y^{(4)}$ of matter fields are written by a product of 3-point couplings $y^{(3)}$ of matter…

High Energy Physics - Phenomenology · Physics 2022-04-06 Tatsuo Kobayashi , Hajime Otsuka , Morimitsu Tanimoto , Kei Yamamoto

Treating the MSSM as an effective theory below a threshold scale Lambda, we study the consequences of having dimension-five operators in the superpotential for flavour and CP-violating processes. Below the supersymmetric threshold such…

High Energy Physics - Phenomenology · Physics 2008-11-26 Maxim Pospelov , Adam Ritz , Yudi Santoso

We discuss the role of flavour physics in building effective theories at the TeV scale. Particular attention is devoted to the Minimal Flavour Violation hypothesis, both in the quark and in the lepton sector. Alternative flavour-protection…

High Energy Physics - Phenomenology · Physics 2009-08-05 Gino Isidori

We present a supersymmetric flavour model based on the T' discrete group, which explains fermion masses and mixings. The flavour symmetry, acting in the supersymmetric sector, provides well defined sfermion mass matrices and the resulting…

High Energy Physics - Phenomenology · Physics 2011-08-24 Luca Merlo

The gauge sector of the Standard Model (SM) exhibits a flavour symmetry which allows for independent unitary transformations of the fermion multiplets. In the SM the flavour symmetry is broken by the Yukawa couplings to the Higgs boson, and…

High Energy Physics - Phenomenology · Physics 2013-05-29 Th. Feldmann , M. Jung , Th. Mannel

We posit that the distinct patterns observed in fermion masses and mixings are due to a minimally broken $\mathrm{U}(2)_{q+e}$ flavor symmetry acting on left-handed quarks and right-handed charged leptons, giving rise to an accidental…

High Energy Physics - Phenomenology · Physics 2024-02-28 Stefan Antusch , Admir Greljo , Ben A. Stefanek , Anders Eller Thomsen

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 show how two different family symmetries can be used to address the flavour problem in SO(10)-like models. The first is based on a gauged $U(1)_F$, whose problems dissappear in the context of a type I string model embedding. The second…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. F. King , I. N. R. Peddie

The Standard Model Effective Field Theory (SMEFT) provides a robust framework for probing deviations in the couplings of Standard Model particles from their theoretical predictions. This framework relies on an expansion in…

High Energy Physics - Phenomenology · Physics 2025-01-22 Nilabhra Adhikary , Tisa Biswas , Joydeep Chakrabortty , Christoph Englert , Michael Spannowsky

Charged lepton flavour-violating (cLFV) processes, which are definite proof of new physics beyond the Standard Model, have remained elusive experimentally till now. Effective Field Theory (EFT) has been very useful in providing information…

High Energy Physics - Phenomenology · Physics 2026-01-06 Utpal Chattopadhyay , Debottam Das , Rahul Puri , Joydeep Roy

We investigate the information that can be gained by including flavour data in fits of the Standard Model Effective Field Theory (SMEFT) with the assumption of Minimal Flavour Violation (MFV), allowing - as initial conditions at the high…

High Energy Physics - Phenomenology · Physics 2021-01-05 Rafael Aoude , Tobias Hurth , Sophie Renner , William Shepherd

After we study the 6-dimensional ${\cal N} = (1, 1)$ supersymmetry breaking and $R$ symmetry breaking on $M^4\times T^2/Z_n$, we construct two ${\cal N} = (1, 1)$ supersymmetric $E_6$ models on $M^4\times T^2/Z_3$ where $E_6$ is broken down…

High Energy Physics - Phenomenology · Physics 2014-11-17 Tianjun Li

The Standard Model Effective Field Theory (SMEFT) provides a consistent framework for comparing precision measurements at the LHC to the Standard Model. The observation of statistically significant non-zero SMEFT coefficients would…

High Energy Physics - Phenomenology · Physics 2021-04-27 Sally Dawson , Samuel Homiller , Samuel D. Lane

We consider a SU(5) x U(1)_F GUT-flavor model in which the number of effects that determine the charged fermions Yukawa matrices is much larger than the number of observables, resulting in a hierarchical fermion spectrum with no particular…

High Energy Physics - Phenomenology · Physics 2008-11-26 Luis F. Duque , Diego A. Gutierrez , Enrico Nardi , Jorge Norena