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Related papers: Inequalities for Standard Model Yukawa Couplings

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We consider the possibility that the neutral-current $B$ anomalies are due to radiative corrections generated by Yukawa interactions of quarks and leptons with new vector-like quark and lepton electroweak doublets and new Standard Model…

High Energy Physics - Phenomenology · Physics 2018-12-27 B. Grinstein , S. Pokorski , G. G. Ross

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

In this paper, we present a formalism for computing the Yukawa couplings in heterotic standard models. This is accomplished by calculating the relevant triple products of cohomology groups, leading to terms proportional to Q*H*u, Q*Hbar*d,…

High Energy Physics - Theory · Physics 2010-12-03 Volker Braun , Yang-Hui He , Burt A. Ovrut

We study the non-Hermitian extension of the Lagrangian of the Standard Model extended by singlet right-handed heavy neutrinos. The Yukawa coupling matrices comprise of hermitian and non-hermitian components and the neutrino mass eigenvalues…

High Energy Physics - Phenomenology · Physics 2023-02-07 Sasmita Mishra

We study the implications of single leptoquark extensions of the Standard Model (SM) under the assumption that their enhanced Yukawa sectors are invariant under global Abelian flavour symmetries already present in SM mass terms. Such…

High Energy Physics - Phenomenology · Physics 2022-10-19 Ivo de Medeiros Varzielas , Jim Talbert

Spontaneously broken Abelian gauge symmetries can explain the fermion mass hierarchies of the minimal supersymmetric standard model. In most cases it is assumed that the $U(1)_H$ symmetry is anomalous. However, non-anomalous models are also…

High Energy Physics - Phenomenology · Physics 2007-05-23 Enrico Nardi

We investigate the quark masses and mixings by including vector-like down-type quark singlets in universality of strength for Yukawa couplings (USY). In contrast with the standard model with USY, the sufficient $ CP $ violation is obtained…

High Energy Physics - Phenomenology · Physics 2009-11-11 Katsuichi Higuchi , Masato Senami , Katsuji Yamamoto

We put forward a model, or rather a relatively broad class of models, beyond the Standard Model based on the two main assumptions: MPP) The coupling constants should be fixed such as to ensure that there be many ``vacuum states'', i.e.…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. L. Bennett , C. D. Froggatt , H. B. Nielsen

We propose that the flavor structure of the quark sector of the Standard Model is determined by a vectorial SU(2) flavor symmetry, which we dub Flavorspin, under which quarks transform as triplets. The fundamental Yukawa couplings are real…

High Energy Physics - Phenomenology · Physics 2015-07-03 Jeffrey Berryman , Daniel Hernández

Motivated by the fermion mass hierarchy we study the phenomenology of two flavorful two-Higgs-doublet model (2HDM) scenarios. By virtue of the flavor or singular alignment ansatz it is possible to link the mass of a subset of fermions to…

High Energy Physics - Phenomenology · Physics 2021-08-25 J. L. Diaz-Cruz , U. J. Saldana-Salazar , K. M. Tame-Narvaez , V. T. Tenorth

We present results for the renormalized quartic self-coupling $\lambda_R$ and the Yukawa coupling $y_R$ in a lattice fermion-Higgs model with two SU(2)$_L$ doublets, mostly for large values of the bare couplings. One-component (`reduced')…

High Energy Physics - Lattice · Physics 2009-10-22 Wolfgang Bock , Christoph Frick , Jan Smit , Jeroen C. Vink

Motivated by the principle of natural flavour conservation, searches for signatures of a second scalar doublet at the LHC are usually limited to models with a very restricted Yukawa structure. Strong correlations between the scalar…

High Energy Physics - Phenomenology · Physics 2015-05-05 Alejandro Celis

A mechanism to generate realistic fermion mass hierarchies based on supersymmetric gauged $U(1)_F$ symmetry in flat five-dimensional (5D) spacetime is proposed. The fifth dimension is compactified on $S^1/Z_2$ orbifold. The standard model…

High Energy Physics - Phenomenology · Physics 2021-06-25 Ketan M. Patel

Recently, we proposed a unified mass matrix model for quarks and leptons, in which, mass ratios and mixings of the quarks and neutrinos are described by using only the observed charged lepton mass values as family-number-dependent…

High Energy Physics - Phenomenology · Physics 2016-08-03 Yoshio Koide , Hiroyuki Nishiura

It is shown that the so-called "Yukawaon" model can give a unified description of masses, mixing and $CP$ violation parameters of quarks and leptons without using any hierarchical (family number-dependent) parameters besides the charged…

High Energy Physics - Phenomenology · Physics 2015-10-22 Yoshio Koide , Hiroyuki Nishiura

In the so-called ``yukawaon" model, the (effective) Yukawa coupling constants $Y_f^{eff}$ are given by vacuum expectation values (VEVs) of scalars $Y_f$ (yukawaons) with $3\times 3$ components. In the present model, all of the VEV matrices…

High Energy Physics - Phenomenology · Physics 2015-06-10 Yoshio Koide , Hiroyuki Nishiura

The tree level potential for a scalar multiplet of `Yukawa fields' $Y$ for one type of quarks admits the promising vacuum configuration $<Y> \propto {\rm diag}(0,0,1)$ that breaks spontaneously $SU(3)_L\times SU(3)_R$ flavour symmetry. We…

High Energy Physics - Phenomenology · Physics 2015-06-12 Jose R. Espinosa , Chee Sheng Fong , Enrico Nardi

We present the results of a numerical search for the Dirac Yukawa matrices of the Standard Model, consistent with the quark and lepton masses and their mixing angles. We assume a diagonal up-quark matrix, natural in $\bs{\m Z_7 \rtimes \m…

High Energy Physics - Phenomenology · Physics 2014-07-16 Jennifer Kile , M. Jay Pérez , Pierre Ramond , Jue Zhang

A grand unified $SU(5)$ theory is constructed with a hierarchical breaking of a $U(2)$ flavor symmetry. The small parameters of the squark and slepton mass matrices, necessary to solve the supersymmetric flavor-changing problem, and the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Riccardo Barbieri , Lawrence Hall

Extended electroweak scalar sectors containing several doublet multiplets require flavour-aligned Yukawa matrices to prevent the appearance at tree level of unwanted flavour- changing neutral-current transitions. We analyse the misalignment…

High Energy Physics - Phenomenology · Physics 2017-12-19 Ana Peñuelas , Antonio Pich