Related papers: Top mixing in effective theories
The applications of effective lagrangians to the determination of the effects of physics beyond the Standard Model are briefly described. Emphasis is given to those effective operators which generate the largest deviations form the Standard…
Nonrelativstic effective field theories have shown to be a useful framework to describe systems of weakly bound particles. This work focuses on the matching procedure to the underlying relativistic theory. The concept of a physical mass in…
We use recent experimental data on charmed mesons to constrain three coupling constants in the effective lagrangian describing the interactions of excited heavy-light mesons with light pseudoscalar mesons at order $m_Q^{-1}$. Predictions in…
The standard model of particle physics is an extremely successful theory of fundamental interactions, but it has many known limitations. It is therefore widely believed to be an effective field theory that describes interactions near the…
We emphasise that even in the extreme chiral limit where only the top and bottom quarks acquire mass, quark mixing is physically meaningful. This implies that the natural value of $|V_{13}|^2 + |V_{23}|^2$ is of order one, which is to be…
Anomalously light fermionic partners of the top quark often appear in explicit constructions, such as the 5d holographic models, where the Higgs is a light composite pseudo Nambu-Goldstone boson and its potential is generated radiatively by…
We construct a modification of the standard model which stabilizes the Higgs mass against quadratically divergent radiative corrections, using ideas originally discussed by Lee and Wick in the context of a finite theory of quantum…
We have continued the development of Lagrangian, cosmological perturbation theory for the low-order correlators of the matter density field. We provide a new route to understanding how the effective field theory (EFT) of large-scale…
Top physics provides a fertile ground for new-physics searches. At present, most top observables appear to be in good agreement with the respective Standard Model predictions. However, in the case of decay modes that are suppressed in the…
Vector-like quarks, usually dubbed top partners, are a common presence in composite Higgs models. Being composite objects, their mass is expected to be of the order of their inverse size, that is the condensation scale of the new strong…
We analyze the corrections to the precision EW observables in minimal composite Higgs models by using a general effective parametrization which also includes the lightest fermionic resonances. A new, possibly large, logarithmically…
A data sample containing top quark pairs ($\mathrm{t\bar{t}}$) produced in association with a Lorentz-boosted Z or Higgs boson is used to search for signs of new physics using effective field theory. The data correspond to an integrated…
The top quark flavor changing neutral current processes are extremely suppressed within the Standard Model. Nevertheless, they could be enhanced in a new physics model beyond the Standard Model. Investigating the top quark's flavor changing…
We present a systematic procedure to obtain the one-loop low-energy effective Lagrangian resulting from integrating out the heavy fields of a given ultraviolet theory. We show that the matching coefficients are determined entirely by the…
In the framework of strongly interacting dynamics for electroweak symmetry breaking, heavy composite particles may arise and cause observable effects, as they should couple strongly to the resulting Higgs boson and affect the signals that…
In this talk I discuss the widespread impact of the top quark on phenomena in elementary particle physics as codified through the Standard Model (SM), its important role in motivating the possiblity of physics beyond the Standard Model…
With the LHC entering the precision era, focus on interpreting the measurements performed in an effective field theory holds key to testing the Standard Model. An effective field theory provides a well-defined theoretical formalism which…
Composite Higgs models, together with partial compositeness, predict the existence of new scalars and vector-like quarks (partners) at and above the TeV scale. Generically, the presence of these additional scalars opens up new decay…
Measurements of the top quark by the ATLAS and CMS experiments go beyond testing the Standard Model (SM) with high precision. Axion-like particles (ALPs), a potential SM extension involving new pseudoscalar particles, exhibit strong…
The latest results on top quark physics, namely single top quark production cross sections, $W$-boson helicity and asymmetry measurements are used to probe the Lorentz structure of the $Wtb$ vertex. The increase of sensitivity to new…