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Related papers: Flavor Constraints from Unitarity and Analyticity

200 papers

We study the implications of an approximate $U(2)^5$ flavor symmetry at the TeV scale, under the assumption of new physics predominantly coupled to the third-generation fermions, focusing on the breaking of the $U(2)_\ell$ subgroup…

High Energy Physics - Phenomenology · Physics 2025-11-21 Sebastiano Covone , Pol Morell , Arianna Tinari

We report the findings of our extensive study of the spectra of flavoured mesons in lattice gauge theories with symplectic gauge group and fermion matter content treated in the quenched approximation. For the $Sp(4)$, $Sp(6)$, and $Sp(8)$…

High Energy Physics - Lattice · Physics 2024-04-17 Ed Bennett , Jack Holligan , Deog Ki Hong , Jong-Wan Lee , C. -J. David Lin , Biagio Lucini , Maurizio Piai , Davide Vadacchino

We consider the effect of a non-zero lattice spacing on the low-energy effective theory of Wilson fermions with one flavor. Analytical results are given for both the chiral condensate and the microscopic spectral density of the Wilson Dirac…

High Energy Physics - Theory · Physics 2015-05-30 Rasmus Normann Larsen

We derive model-independent constraints arising from the Z and W boson observables on dimension six operators in the effective theory beyond the Standard Model. In particular, we discuss the generic flavor structure for these operators as…

High Energy Physics - Phenomenology · Physics 2015-08-04 Aielet Efrati , Adam Falkowski , Yotam Soreq

We review the modular flavor symmetric models of quarks and leptons focusing on our works. We present some flavor models of quarks and leptons by using finite modular groups and discuss the phenomenological implications. The modular flavor…

High Energy Physics - Phenomenology · Physics 2023-07-19 Tatsuo Kobayashi , Morimitsu Tanimoto

Heavy neutral leptons (HNLs) are hypothetical particles proposed as a potential explanation for neutrino oscillations and the generation of the baryon asymmetry in the Universe. This paper focuses on HNLs with masses significantly above the…

High Energy Physics - Phenomenology · Physics 2025-02-11 Volodymyr Gorkavenko , Oleksandr Khasai , Oleg Ruchayskiy , Mariia Tsarenkova

Partial compositeness is a key ingredient of models where the electroweak symmetry is broken by a composite Higgs state. Recently, a UV completion of partial compositeness was proposed, featuring a new strongly coupled gauge interaction as…

High Energy Physics - Phenomenology · Physics 2018-07-04 Francesco Sannino , Peter Stangl , David M. Straub , Anders Eller Thomsen

We consider a class of models predicting new heavy neutral fermionic states, whose mixing with the light neutrinos can be naturally significant and produce observable effects below the threshold for their production. We update the indirect…

High Energy Physics - Phenomenology · Physics 2016-09-01 D. Tommasini , G. Barenboim , G. Bernabeu , C. Jarlskog

We consider processes which produce final state hadrons whose energy is much greater than their mass. In this limit interactions involving collinear fermions and gluons are constrained by a symmetry, and we give a general set of rules for…

High Energy Physics - Phenomenology · Physics 2011-05-05 Christian W. Bauer , Iain W. Stewart

Lepton flavour violation has been proposed as a significant test of supersymmetric unification. Here we show that such signals are also a generic feature of supersymmetric string unified models in which there is no simple unified gauge…

High Energy Physics - Phenomenology · Physics 2016-08-25 S. F. King , M. Oliveira

We present a global likelihood function in the space of dimension-six Wilson coefficients in the Standard Model Effective Field Theory (SMEFT). The likelihood includes contributions from flavour-changing neutral current B decays, lepton…

High Energy Physics - Phenomenology · Physics 2019-07-24 Jason Aebischer , Jacky Kumar , Peter Stangl , David M. Straub

We explore the constraints which can be derived on Wilson coefficients in the Standard Model Effective Field Theory from dilepton production, notably including the constraints on operators which do not lead to cross sections growing with…

High Energy Physics - Phenomenology · Physics 2021-03-31 Alyssa Horne , Jordan Pittman , Marcus Snedeker , William Shepherd , Joel W. Walker

Staggered fermions with 4 tastes are expected to describe 4-flavor QCD in the continuum limit, therefore at finite lattice spacing the staggered determinant should be equivalent to an SU(4) flavor-symmetric system up to lattice artifacts.…

High Energy Physics - Lattice · Physics 2007-05-23 Anna Hasenfratz

We explore the limits on lepton-flavor universality (LFU) violation in theories where the hierarchy problem is solved by means of a warped extra dimension. In those theories LFU violation, in fermion interaction with Kaluza-Klein modes of…

High Energy Physics - Phenomenology · Physics 2017-11-01 Eugenio Megias , Mariano Quiros , Lindber Salas

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

We show that the fermionic exclusion principle in scattering problems manifests itself through constraints implied by unitarity and the optical theorem. Configurations that formally allow identical fermions to appear in the same quantum…

High Energy Physics - Phenomenology · Physics 2026-05-01 Peter Matak

Although the $(g-2)_\mu$ anomaly can be explained by New Physics (NP) involving only muons, a more general flavor structure is usually expected for NP operators in the Standard Model (SM) Effective Field Theory (SMEFT). In particular, if…

High Energy Physics - Phenomenology · Physics 2022-05-30 Julie Pagès

Whenever an anomaly in the flavour sector appears, analyses are performed examining whether it can be explained by adding a small number of carefully-chosen flavour non-universal four-fermion SMEFT operators. These analyses are typically…

High Energy Physics - Phenomenology · Physics 2026-03-05 Alakabha Datta , Jean-François Fortin , Jacky Kumar , David London , Danny Marfatia , Nicolas Sanfaçon

We analyze the bounds on the spectrum of composite Higgs models (CHM) that come from flavor observables, by means of simple two-site effective Lagrangians, which incorporate a custodial symmetry and a Left-Right parity and which could also…

High Energy Physics - Phenomenology · Physics 2012-12-06 Natascia Vignaroli

We present an updated and improved global fit analysis of current flavor and electroweak precision observables to derive bounds on unitarity deviations of the leptonic mixing matrix and on the mixing of heavy neutrinos with the active…