Results 151 to 160 of about 1,453 (168)

Pathways to Unification with Vector Like Fermions

Springer Proceedings in Physics, 2020
We present a minimal extensions of Standard Model with TeV scale vector like fermions which leads to unification of gauge couplings. Model has been constraints from proton decay, Higgs stability and perturbativity. The simplest models contain copies of vector like fermions in two different (incomplete) representations. Some models enclose SU(2) triplet,
Sudhir Vempati, Biplob Bhattacherjee
exaly   +2 more sources

ΔF=2 effective Lagrangian in theories with vector-like fermions [PDF]

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 1998
18 pages, Latex, 9 figures. Typos and misprints were corrected and some references added. To appear in Phys.
G Barenboim, F J Botella
exaly   +4 more sources

On the phase structure of vector-like gauge theories with massless fermions

Nuclear Physics B, 1982
Abstract We present a systematic expansion for studying an infrared-stable fixed point of gauge theories with massless fermions. These results are combined with information from strong coupling and large-NF expansions to sketch the phase diagrams for lattice gauge theories with massless fermions.
T Banks
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Scalar Resonance at 750 GeV as Composite of Heavy Vector-Like Fermions [PDF]

Communications in Theoretical Physics, 2016
12 pages, no figure, references updated, version for ...
Liao, Wei, Zheng, Han-qing
exaly   +3 more sources

SO(10) models for flavor with vector-like fermions

AIP Conference Proceedings, 2017
In this work, unified models based on S O(10) symmetry is presented which provides insights into the flavor observables of charged fermions and the neutrinos. Unlike the conventional S O(10) models, the Higgs boson 10H belonging to the fundamental representation is not present in this new class of models.

exaly   +2 more sources

Vector-like fermions could enhance the B− mixing

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 1989
Abstract The possibility of enhancing the B− b mixing without a large top mass is proposed within the context of theories which enlarge the standard model by new heavy down quarks, isosinglets under SU(2) × U(1). A model which realizes this idea is shown.
exaly   +2 more sources

Constraining models with vector-like fermions from FCNC in K and B physics [PDF]

Nuclear Physics B, 2001
In this work, we update the constraints on tree level FCNC couplings in the framework of a theory with n isosinglet vector-like down quarks. In this context, we emphasize the sensitivity of the B -> J/psi K_S CP asymmetry to the presence of new vector-like down quarks. This CP asymmetry, together with the rare decays B -> X_{s,d} l bar{l} and K -&
Oscar Vives, G Barenboim, F J Botella
exaly   +4 more sources

ELECTRIC CHARGE QUANTIZATION AND VECTOR-LIKE FERMIONS

Modern Physics Letters A, 1990
In extended gauge models with gauge group G, electric charge quantization is not always an automatic consequence of the consistency of the theory. Exotic fermions which have SU (3) ⊗ SU (2) L ⊗ U (1) invariant mass terms can provide a simple method for preserving the charge quantization feature of the standard model.
openaire   +1 more source

Muon g-2 and dark matter in models with vector-like fermions [PDF]

Proceedings of The European Physical Society Conference on High Energy Physics — PoS(EPS-HEP2017), 2018
We investigate simplified models of new physics that can accommodate the measured value of the anomalous magnetic moment of the muon and the relic density of dark matter. We define a set of renormalizable, SU(2)$\times$U(1) invariant extensions of the Standard Model, each comprising an inert $\mathbb{Z}_2$-odd scalar field and one or more vector ...
Enrico Maria Sessolo, Kamila Kowalska
exaly   +2 more sources

Light vector-like fermions in a minimal SU(5) setup

Physical review. D, Particles, fields, gravitation, and cosmology, 2014
The Standard Model fermion sector is enlarged by either one light singlet vector-like down- type quark or one light vector-like lepton doublet, which might be accommodated within a five- dimensional representation of SU(5). At low energies the inclusion of these states affects precisely measured observables in flavor physics, as well as electroweak ...
Doršner, Ilja, Fajfer, Svjetlana
openaire   +1 more source