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Related papers: Light fermions in composite models

200 papers

In the Standard Model of elementary particles the fermions are assumed to be intrinsically massless. Here we propose a new theoretical idea of fermion mass generation (other than by the Higgs mechanism) through the coupling with the vector…

High Energy Physics - Phenomenology · Physics 2025-08-26 Eckart Marsch , Yasuhito Narita

We propose a renormalizable theory based on the $SU(3)_C\times SU(3)_L\times U(1)_X$ gauge symmetry, supplemented by the spontaneously broken $U(1)_{L_g}$ global lepton number symmetry and the $S_3 \times Z_2 $ discrete group, which…

High Energy Physics - Phenomenology · Physics 2021-03-08 A. E. Cárcamo Hernández , Yocelyne Hidalgo Velásquez , Sergey Kovalenko , H. N. Long , Nicolás A. Pérez-Julve , V. V. Vien

Different approaches to the fermion mass problem are reviewed. We illustrate these approaches by summarizing recent developments in models of quark and lepton mass matrices. Dynamical calculations of the top quark mass are discussed, based…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt

We propose a renormalizable theory with minimal particle content and symmetries, that successfully explains the number of Standard Model (SM) fermion families, the SM fermion mass hierarchy, the tiny values for the light active neutrino…

High Energy Physics - Phenomenology · Physics 2020-09-16 A. E. Cárcamo Hernández , D. T. Huong , H. N. Long

We study the excitations of hadrons containing a single heavy quark. We present meson and baryon mass splittings and ratios of meson decay constants resulting from quenched and dynamical two-flavor configurations. Light quarks are simulated…

High Energy Physics - Lattice · Physics 2010-01-21 Tommy Burch , Christian Hagen , Christian B. Lang , Markus Limmer , Andreas Schäfer

We summarize the results showing that all existing data on mixing between up and down fermion states (i.e. CKM matrix and neutrino oscillations) and on the hierarchical quark and lepton mass ratios between generations are consistent with…

High Energy Physics - Phenomenology · Physics 2009-11-10 ST Tsou , JS Palmer

Fermion mass matrices generally rotate in generation space under scale changes, which can lead to fermions of different generations transmuting into one another. The effect is examined in detail and its cross-section calculated for $\gamma…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. T. Tsou

A new mechanism is presented for the generation of quark and lepton masses, based on a heavy fourth family and a new sector of massless fermions. The massless fermions have only discrete chiral symmetries and they are confined by the…

High Energy Physics - Phenomenology · Physics 2009-10-22 B. Holdom

We present a phenomenological ansatz for coupling a heavy quark with two light quarks to form a heavy baryon. The heavy quark is treated in the heavy mass limit, and the light quark dynamics is approximated by propagating scalar and axial…

High Energy Physics - Phenomenology · Physics 2009-10-28 D. Ebert , T. Feldmann , C. Kettner , H. Reinhardt

We use the idea of partial compositeness in a minimal supersymmetric model to relate the fermion and sfermion masses. By assuming that the Higgs and third-generation matter is (mostly) elementary, while the first- and second-generation…

High Energy Physics - Phenomenology · Physics 2019-03-27 Yusuf Buyukdag , Tony Gherghetta , Andrew S. Miller

We propose a low scale renormalizable left-right symmetric theory that successfully explains the observed SM fermion mass hierarchy, the tiny values for the light active neutrino masses and is consistent with the lepton and baryon…

High Energy Physics - Phenomenology · Physics 2022-03-02 A. E. Cárcamo Hernández , Ivan Schmidt

The weak bosons, leptons and quarks are considered as composite particles. The interaction of the constituents is a confining gauge interaction. The standard electroweak model is a low energy approximation. The mixing of the neutral weak…

High Energy Physics - Phenomenology · Physics 2010-11-05 Harald Fritzsch

We explore quark interactions mediated by new gauge bosons of masses in the 0.3 - 50 GeV range. A tight upper limit on the gauge coupling of light Z' bosons is imposed by the anomaly cancellation conditions in conjunction with collider…

High Energy Physics - Phenomenology · Physics 2014-08-13 Bogdan A. Dobrescu , Claudia Frugiuele

In modular-invariant models of flavour, hierarchical fermion mass matrices may arise solely due to the proximity of the modulus $\tau$ to a point of residual symmetry. This mechanism does not require flavon fields, and modular weights are…

High Energy Physics - Phenomenology · Physics 2024-06-11 P. P. Novichkov , J. T. Penedo , S. T. Petcov

We show that in a self-consistent preon model, where Standard Model quarks and leptons are three-body composites confined at a metacolor scale Lambda_cr ~ 10^14 GeV, both leptoquarks and the Standard Model gauge group SU(3)_c x SU(2)_L x…

High Energy Physics - Phenomenology · Physics 2026-05-01 Risto Raitio

Chiral fermions can (presumably) be constructed by introducing two regulators, one for the gauge fields (e.g. a lattice), and another for the fermion functional integrals in a fixed (regulated) gauge field. This talk discusses cutoff…

High Energy Physics - Lattice · Physics 2009-10-28 Andreas S. Kronfeld

We study perturbative unitarity constraints on general W' models by considering the high energy behavior of fermion scattering into gauge bosons. In most cases we survey, a Z' boson with a comparable mass must be present for the theory to…

High Energy Physics - Phenomenology · Physics 2015-06-03 K. S. Babu , J. Julio , Yue Zhang

The interactions of $\rho$, $K^*$, $\phi$ and $\omega$ vector-mesons with low-momentum $\pi$, $K$ and $\eta$ pseudoscalar mesons are constrained by chiral symmetry. We derive a heavy vector-meson chiral Lagrangian in which the vector mesons…

High Energy Physics - Phenomenology · Physics 2008-11-26 Elizabeth Jenkins , Aneesh V. Manohar , Mark B. Wise

We examine the possibility of fermion mass generation in 2+1- dimensional gauge theory from the current algebra point of view.In our approach the critical behavior is governed by the fluctuations of pions which are the Goldstone bosons for…

High Energy Physics - Phenomenology · Physics 2009-10-22 M. C. Diamantini G. W. Semenoff P. Sodano

The issue of chiral extrapolations in heavy quarkonium systems is discussed. We show that the light quark mass dependence of the properties of heavy quarkonia is not always suppressed. For quarkonia close to an open flavor threshold, even a…

High Energy Physics - Phenomenology · Physics 2012-08-13 Feng-Kun Guo , Ulf-G. Meißner