Related papers: Feasible Deviations from Unitarity with Vector-Lik…
The Littlest Higgs model contains a new vector-like heavy quark in the up sector. There are two interesting features of its existence. One is that it extends the $3\times3$ CKM matrix in the Standard Model to a $4\times3$ matrix and the…
A unified description of fermionic mixing is proposed which assumes that in certain basis ($i$) a single complex unitary matrix $V$ diagonalizes mass matrices of all fermions to the leading order, ($ii$) the SU(5) relation $M_d=M_l^T$…
The VuQ model involves the addition of a vector isosinglet up-type quark to the standard model. In this model the full CKM quark mixing matrix is 4 X 3. Using present flavor-physics data, we perform a fit to this full CKM matrix, looking…
The existence of new vector-like quarks is often predicted by models of new physics beyond the Standard Model, and the development of discovery strategies at colliders is the object of an intense effort from the high-energy community. Our…
We investigate a flexible method in which we can test the unitarity of the quark flavor mixing matrix step-by-step. Singular-Value-Decomposition (SVD) techniques are used in analyzing the mixing matrix over a broader parameter region than…
We study the patterns of flavour violation in renormalisable extensions of the Standard Model (SM) that contain vector-like quarks (VLQs) in a single complex representation of either the SM gauge group $G_{SM}$ or $G_{SM}' = G_{SM} \times…
The present status of universality tests of the weak couplings for quarks and leptons is reviewed, with updated information for the muon lifetime and for first-row inputs in the CKM matrix. We discuss the impact of this high-precision SM…
Dark Matter (DM) is a known unknown. Apart, current experimental constraints on flavor-changing neutral current (FCNC) processes involving up-type quarks also provide scope to explore physics beyond the Standard Model (SM). In this article,…
The unitarity of the CKM matrix is examined in the light of the latest available accurate data. The analysis shows that for the elements in the first row, there are two types of experimental measurements leading to different results for the…
We propose a minimal extension of the Standard Model where an up-type vector-like quark, denoted $T$, is introduced and provides a simple solution to the CKM unitarity problem. We adopt the Botella-Chau parametrization in order to extract…
We analyse a possible connection between CP violations in the quark and lepton sectors, parametrised by the CKM and PMNS phases. If one assumes that CP breaking arises from complex Yukawa couplings, both in the quark and lepton sectors, the…
In this talk we emphasise the importance of vector-like quarks (VLQs) and their potential to solve some of the open questions of the Standard Model. These are, in some sense minimal extensions of the Standard Model, that can be probed in…
We examine the prospects for LHC discovery of SU(2)_L singlet vector-like quarks that obey Minimal Flavour Violation (MFV) and are consistent with lower energy phenomenology. We study models where the vector-like quarks have the same…
In this work, we present a comprehensive review of the most up-to-date exclusion limits on Vector-Like Quarks (VLQs) derived from ATLAS and CMS data at the Large Hadron Collider (LHC). Our analysis encompasses both pair and single…
Minimal Flavour Violation in its strong or weak versions, based on $U(3)^3$ and $U(2)^3$ respectively, allows suitable extensions of the Standard Model at the TeV scale to comply with current flavour constraints in the quark sector. Here we…
A simple breaking of the subnuclear democracy of the quarks leads to a mixing between the second and the third family, in agrement with observation. Introducing the mixing between the first and the second family, one finds an interesting…
We estimate the CKM matrix elements in the recently proposed minimal model, anti-SU(7) GUT for the family unification, $[\,3\,]+2\,[\,2\,]+8\,[\,\bar{1}\,]$+\,(singlets). It is shown that the real angles of the right-handed unitary matrix…
We investigate the experimentally allowed parameter space of an extension of the standard model (SM3) by one additional family of fermions. Therefore we extend our previous study of the CKM like mixing constraints of a fourth generation of…
We study a model with a down-type SU(2) singlet vector-like quark (VLQ) as a minimal extension of the standard model (SM). In this model, flavor changing neutral currents (FCNCs) arise at tree level and the unitarity of the $3\times 3$…
We construct a model of quark-lepton unification at the TeV scale based on an $SU(4)$ gauge symmetry, while still having acceptable neutrino masses and enough suppression in flavor changing neutral currents. An approximate $U(2)$ flavor…