Results 1 to 10 of about 20,447 (286)
U(1) flavour symmetries as Peccei-Quinn symmetries [PDF]
Journal of High Energy Physics, 2019 We investigate to what extent a generic, generation-dependent U(1) symmetry acting on the quark Yukawa operators can reduce the number of free parameters by forcing some entries in the Yukawa matrices to vanish.
Fredrik Björkeroth +3 more
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Flavour symmetries in the SMEFT [PDF]
Journal of High Energy Physics, 2020 We analyse how U(3)5 and U(2)5 flavour symmetries act on the Standard Model Effective Field Theory, providing an organising principle to classify the large number of dimension-six operators involving fermion fields. A detailed counting of such operators,
Darius A. Faroughy +3 more
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Accidental Peccei–Quinn symmetry from discrete flavour symmetry and Pati–Salam
Physics Letters B, 2018 We show how an accidental U(1) Peccei–Quinn (PQ) symmetry can arise from a discrete A4 family symmetry combined with a discrete flavour symmetry Z3×Z52, in a realistic Pati–Salam unified theory of flavour. Imposing only these discrete flavour symmetries,
Fredrik Björkeroth +2 more
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Symmetry constrained two Higgs doublet models
European Physical Journal C: Particles and Fields, 2018 We study two-Higgs-doublet models (2HDM) where Abelian symmetries have been introduced, leading to a drastic reduction in the number of free parameters in the 2HDM.
João M. Alves +5 more
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Dipole operator constraints on composite Higgs models. [PDF]
Eur Phys J C Part Fields, 2014 Flavour- and CP-violating electromagnetic or chromomagnetic dipole operators in the quark sector are generated in a large class of new physics models and are strongly constrained by measurements of the neutron electric dipole moment and observables ...
König M, Neubert M, Straub DM.
europepmc +2 more sources
Predictions from a flavour GUT model combined with a SUSY breaking sector
Journal of High Energy Physics, 2017 We discuss how flavour GUT models in the context of supergravity can be completed with a simple SUSY breaking sector, such that the flavour-dependent (non-universal) soft breaking terms can be calculated.
Stefan Antusch, Christian Hohl
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Implications of the Muon g-2 result on the flavour structure of the lepton mass matrix
European Physical Journal C: Particles and Fields, 2021 The confirmation of the discrepancy with the Standard Model predictions in the anomalous magnetic moment by the Muon g-2 experiment at Fermilab points to a low scale of new physics.
Lorenzo Calibbi +3 more
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European Physical Journal C: Particles and Fields, 2023 We investigate flavour bounds on the $${\mathcal {Z}}_2 \times {\mathcal {Z}}_5$$ Z 2 × Z 5 and $${\mathcal {Z}}_2 \times {\mathcal {Z}}_9$$ Z 2 × Z 9 flavour symmetries.
Gauhar Abbas +3 more
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Two A4 modular symmetries for Tri-Maximal 2 mixing
Nuclear Physics B, 2022 We construct a lepton flavour model based on two A4 modular symmetries. The two A4 are broken by a bi-triplet field to the diagonal A4 subgroup, resulting in an effective modular A4 flavour symmetry with two moduli. We employ these moduli as stabilisers,
Ivo de Medeiros Varzielas +1 more
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FCNC-free multi-Higgs-doublet models from broken family symmetries
Physics Letters B, 2020 We demonstrate how residual flavour symmetries, infrared signatures of symmetry breaking in complete models of flavour, can naturally forbid (or limit in a flavour specific way) flavour-changing neutral currents (FCNC) in multi-Higgs-doublet models (MHDM)
Ivo de Medeiros Varzielas, Jim Talbert
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