Related papers: A universally enhanced light-quarks Yukawa couplin…
In various unified extensions of the Minimal Supersymmetric Standard Model, the Yukawa couplings of the third generation are predicted to be of the same order. As a result, low energy measured mass ratios, require large ratios of the…
A general operator expansion is presented for quark and lepton mass matrices in unified theories based on a U(2) flavor symmetry, with breaking parameter of order $V_{cb} \approx m_s/m_b \approx \sqrt{m_c/m_t}$. While solving the…
In the standard model, the Higgs boson $h$ couples to the quarks and charged leptons according to the well-known formula $(m_\psi/v) h \bar{\psi}\psi$, where $\psi$ = quark (q) or lepton (l) and $v$ = 246 GeV is its vacuum expectation…
We have presented a detailed study about the prospects for the measurement of the top Yukawa coupling in the vector boson fusion (VBF) production of a top quark pair at high energy muon colliders. By employing the effective $W$…
We present the full one-loop correction to the relation between the running MSbar Yukawa coupling, $\overline h_f(\mu)$, at some renormalization scale, $\mu$, and the pole mass, $m_f$, of a fermion, $f$, in the standard model. Our result…
One main obstacle for any beyond the SM (BSM) scenario solving the hierarchy problem is its potentially large contributions to electric dipole moments. An elegant way to avoid this problem is to have the light SM fermions couple to the BSM…
To address fermion mass hierarchy and flavor mixings in the quark and lepton sectors, a minimal flavor structure without any redundant parameters beyond phenomenological observables is proposed via decomposition of the Standard Model Yukawa…
We investigate naturalness in the Standard Model (SM) Higgs sector using effective field theory (EFT) techniques and find the requirements on the new heavy physics that can potentially cure the little hierarchy problem below a scale…
The recent discovery of the bottom quark Yukawa coupling ($hbb$) of the 125 GeV scalar motivates one to search for extra bottom Yukawa coupling that may exist in the nature. The two Higgs doublet model without a discrete $Z_2$ symmetry…
We estimate the sensitivity to the top-quark Yukawa coupling $y_t$ at future $e^+e^-$ colliders. We go beyond the standard approach that focuses on $t\bar t h$ production and consider final states with a Higgs boson but not top quarks. The…
I discuss the properties of the minimal supersymmetric extension of the standard model, in the case in which there is a dynamical breakdown of the electroweak symmetry induced by the formation of condensates of the third generation of…
We present a new constraint on a lepton mixing matrix $V$ from lepton-flavor violating (LFV) processes in supersymmetric standard models with massive neutrinos. Here, we assume Yukawa-coupling unification $f_{\nu 3}\simeq f_{\rm top}$, in…
With no direct evidence for new physics at the TeV scale, deviations from the Standard Model (SM) can be explored systematically through Effective Field Theories (EFTs) such as the Standard Model EFT (SMEFT). SMEFT extends the SM by…
We investigate the Yukawa coupling unification for the third generation in a class of $\mathsf{SO(10)}$ unified models which are consistent with the 4.2 $\sigma$ deviation from the standard model of the muon $g-2$ seen by the Fermilab…
The observation of $t\bar th(125)$ production at the Large Hadron Collider (LHC) is the first direct measurement of the top Yukawa coupling. It opens the window on an extra top Yukawa coupling, $\rho_{tt}$, from a second Higgs doublet,…
Yukawa-type interactions between heavy Dirac fermions and a scalar field are a common ingredient in various extensions of the Standard Model. Despite of that, the non-relativistic limit of the scalar Yukawa theory has not yet been studied…
We propose a supersymmetric extension of the anomaly-free and three families nonuniversal $U(1)$ model, with the inclusion of four Higgs doublets and four Higgs singlets. The quark sector is extended by adding three exotic quark singlets,…
A scan of the top quark pair production threshold at a future electron-positron collider provides the possibility for high-precision measurements of the top quark mass, and, when using two dimensional fits of the measured cross sections,…
Theories where the Standard Model fields reside on a 3-brane, with a low fundamental cut-off and extra dimensions, provide alternative solutions to the gauge hierarchy problem. However, generating flavor at the TeV scale while avoiding…
We investigate effective Yukawa couplings of mesons to the elementary fermions in noncompact lattice QED. The couplings are extracted from suitable fermion-antifermion-meson three-point functions calculated by Monte Carlo simulations with…