相关论文: Exotic Vector-Like Quark Phenomenology in the Mini…

We discuss a Little Higgs scenario that introduces below the TeV scale just the two minimal ingredients of these models, a vectorlike T quark and a singlet component (implying anomalous couplings) in the Higgs field, together with a…

We look for minimal extensions of Standard Model with vector like fermions leading to precision unification of gauge couplings. Constraints from proton decay, Higgs stability and perturbativity are considered. The simplest models contain…

A search for singly produced vector-like quarks $Q$, where $Q$ can be either a $T$ quark with charge $+2/3$ or a $Y$ quark with charge $-4/3$, is performed in proton-proton collision data at a centre-of-mass energy of 13 TeV corresponding…

We obtain constraints on the mixing of vector-like quarks coupling predominantly to the third generation. We consider all (seven) relevant types of vector-like quarks, individually. The constraints are derived from oblique corrections and Z…

New vector-like quarks can mix sizably with first generation Standard Model quarks without conflicting with current experimental constraints. Searches for such new quarks have been performed in pair production and electroweak single…

Little Higgs models offer a new way to address the hierarchy problem, and give rise to a weakly-coupled Higgs sector. These theories predict the existence of new states which are necessary to cancel the quadratic divergences of the Standard…

Many models of Beyond the Standard Model physics involve heavy colored fermions. We study models where the new fermions have vector interactions and examine the connection between electroweak precision measurements and Higgs production. In…

We have analysed the observable consequences of the interactions of spin-1 resonances coupled to the invariant fermionic currents that arise in an $SO(5)$ Composite Higgs set-up. The phenomenology entailed by such interactions is thoroughly…

The recent observation of the muon $(g-2)_{\mu}$ anomaly continues to challenge the explanations provided by the Standard Model. However, this anomaly can potentially find reconciliation within the framework of two-Higgs doublet models,…

The discovery of Standard-Model like Higgs at 125 GeV may raise more questions than the answers it provides. In particular, the hierarchy problem remains unsolved, and the Standard Model Higgs quartic self-coupling becomes negative below…

We discuss a mechanism which can reduce the S and T parameters in dynamical electroweak symmetry breaking scenario. It is interesting that not only T but also S parameters can be made small even if large isospin violation exists, which can…

We show how a novel fine-tuning problem present in the Standard Model can be solved through the introduction of a single flavour symmetry G, together with three $Q = - 1/3$ quarks, three $Q = 2/3$ quarks, as well as a complex singlet…

A search for singly produced vector-like $Q$ quarks, where $Q$ can be either a $T$ quark with charge $+2/3$ or a $Y$ quark with charge $-4/3$, is performed in proton-proton collisions recorded with the ATLAS detector at the LHC. The dataset…

We study Little Higgs models based on a SU(3)_1 x SU(3)_2 global symmetry and with two scales (the two vacuum expectation values f_{1,2}) substantially different. We show that all the extra vector boson fields present in these models may be…

We study the decay of the exotic Vector-Like Quarks (VLQs) $X$ and $Y$, with $5/3$ and $-4/3$ units of electric charge, respectively, within the 2-Higgs Doublet Model (2HDM). Building on our previous studies of Vector-Like Top and Bottom…

Numerous phenomenological studies and collider searches have probed for the existence of new physics by looking for signatures of leptoquarks (LQs) or vectorlike leptons (VLLs). We consider a new possibility that can arise in theories with…

We discuss models in which vectorlike quarks and a second Higgs doublet are simultaneously present and couple to the third generation of SM quarks. A general feature of these models is that cascade decays of vectorlike fermions into heavy…

In these proceedings we explore the possibility of new physics manifesting itself in rare top quark decays. In particular, we adopt an effective theory description of FCNC t -> q V top quark decays and possible deviations from the SM form…

A search is presented for single production of a vector-like $B$ quark decaying into a Standard Model $b$-quark and a Standard Model Higgs boson, which decays into a $b\bar{b}$ pair. The search is carried out in 139 fb$^{-1}$ of $\sqrt{s} =…

Many models beyond the standard model predict the existence of vector-like quarks or other types of heavy resonances. Using proton-proton collision data at center-of-mass energies of 8 and 13 TeV, the ATLAS and CMS Collaborations have…