Related papers: Are Four-Fermion Operators Relevant for the Fermio…
Beyond the Standard Model scenarios introduce additional scalar and fermion multiplets, which influence neutrino mass generation mechanisms and yield distinctive collider signatures. This work focuses on a particular scenario involving a…
Particle physics models where there are large hidden extra dimensions are currently on the focus of an intense activity. The main reason is that these large extra dimensions may come with a TeV scale for quantum gravity (or string theory)…
SU(2)xU(1) electroweak gauge model without Higgs sector is extended by a new vector field C interacting with leptons and quarks of both chiralities. This interaction is treated under a dynamical assumption in a self-consistent…
The magnetic moment ($a_\gamma$) and weak magnetic moment ($a_W$) of charged leptons and quarks are sensitive to quantum effects of new physics heavy resonances. In effective field theory $a_\gamma$ and $a_W$ are induced by two independent…
We calculate the four-top quark operator contributions to the two-loop renormalization constants of the fermion and gluon fields, necessary to obtain the renormalization group equations for the fermion masses and the strong coupling…
We describe a nonstandard proposal for baryogenesis in models with a low (O(10-100)TeV) fundamental scale. The scenario has Standard Model field content and enhanced baryon number violating operators deriving from time-dependent fermion…
In this paper, we study the triple top quark production at the future high-energy proton-proton colliders to probe the four-fermion interactions involving three top quarks. We employ the Standard Model Effective Field Theory (SMEFT) to find…
A composite model of fermions is proposed to explain the "anomaly" in $Z \rightarrow b {\bar b}$ and, to a lesser extent, in $Z \rightarrow c {\bar c}$. It contains a {\em nonsequential} fourth family whose mass of one member (the charge…
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…
We analyze fermion mass-matrix structure in an asymptotically non-free model with 4 + 1bar generations. The texture at the GUT scale is uniquely determined by supposing that the masses of heavy up-type quarks (charm as well as top) are…
The search for quartic anomalous gauge couplings (QAGC) at LEP requires appropriate predictions for the radiative processes e+ e- \to \nu\bar\nu \gamma\gamma, e+ e- \to q\bar{q}\gamma\gamma and e+ e- \to 4 fermions+\gamma. The current…
The introduction of mirror fermions with masses between the weak scale and 1 TeV could offer a dynamical origin to the standard-model electro-weak symmetry breaking mechanism. The purpose of this work is to study the dynamics needed in…
We study quark and lepton mass matrix textures in a model containing an additional $U(1)_X$ gauge symmetry with origins in string compactification. The $U(1)_X$ symmetry is broken near the string scale, and we assume that the anomalies are…
We study the possibilty to produce single fourth SM family fermions at electron-positron colliders via anomalous gamma-f4-f interactions.
This paper is concerned with a way of thinking about the standard model that explains the existence of three fermion families and the value of the fine structure constant. The main idea is that the ultraviolet divergences that we encounter…
We present a new staggered discretization of the Dirac operator. Doubling gives only a doublet of Dirac fermions which we propose to interpret as a physical (lepton or quark) doublet. If coupled with gauge fields, an $(1+\gamma^5)$ chiral…
Given the eventuality of neutrino and muon factories in the foreseeable future, all possible 2-to-2 processes involving two neutrinos, whether Dirac or Majorana ones, and two charged fermions are considered on the basis of the most general…
An analysis is given of the dynamical symmetry breaking of semi-simple gauge groups. We construct a class of renormalizable gauge theories for the dynamically broken topcolor and technicolor interactions. It is shown that a four-Fermi…
It has recently been proposed that all fundamental fermion masses (whether Dirac or Majorana) come from effective dimension-five operators in the context of a truly minimal left-right model. We show how a particularly economical scheme…
We calculate the splitting between fermion and anti-fermion effective masses in high temperature gauge theories in the presence of a non-vanishing chemical potential due to the $CP$-asymmetric fermionic background. In particular we consider…