Related papers: Mutually elusive: vectorlike antileptons and lepto…
A search for vector-like leptons in multilepton (two, three, or four-or-more electrons plus muons) final states with zero or more hadronic $\tau$-lepton decays is presented. The search is performed using a dataset corresponding to an…
The Standard Model of particle physics currently provides our best description of fundamental particles and their interactions. The theory predicts that the different charged leptons, the electron, muon and tau, have identical electroweak…
We analyze systematically the signatures of vector leptoquarks in hadronic collisions. We examine their single and pair productions, as well as their effects on the production of lepton pairs. Our results indicate that a machine like the…
Three of the most significant measured deviations from standard model predictions, the enhanced decay rate for B $\to$ D$^{(*)}\tau\nu$, hints of lepton universality violation in B $\to$ K$^{(*)}\ell\ell$ decays, and the anomalous magnetic…
We discuss an extension of the standard model (SM) with vector and scalar leptoquarks. The renormalizable leptoquark Lagrangian consistent with the SM gauge symmetry is presented including the leptoquark-Higgs interactions previously not…
New gauge symmetries often appear in theories beyond the Standard Model. Here we study a model where lepton number is promoted to a gauge symmetry. Anomaly cancellation requires the introduction of additional leptons, the lightest of which…
We investigate in detail the LHC phenomenology of "vectorlike confinement", where the Standard Model is augmented by a new confining gauge interaction and new light fermions that carry vectorlike charges under both the Standard Model and…
Flavor symmetries that explain masses and mixings of the standard model fermions dictate flavor patterns for the couplings of scalar and vector leptoquarks to the standard model fermions. A generic feature is that couplings to…
The application of fermion-boson symmetry to the standard model leads to the following: first, there are three generations of scalar quarks and scalar leptons in addition to the known quarks and leptons, and, secondly, the divergences in…
We propose a non-supersymmetric SU(5) model in which only the third family of fermions are unified. The model remedies the non-unification of the three Standard Model couplings in non-supersymmetric SU(5). It also provides a mechanism for…
The decay rate of neutrinoless double beta decay could be dominated by short-range diagrams involving heavy scalar particles ("topology-II" diagrams). Examples are diagrams with diquarks, leptoquarks or charged scalars. Here, we compare the…
We make a comprehensive study of vector-like fermionic dark matter and flavor anomalies in a simple extension of standard model. The model is added with doublet vector-like fermions of quark and lepton types, and also a…
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 extend the left-right symmetric model with an additional non-abelian $SU(2)$ gauge symmetry. The particle content is augmented by one generation of vector-like fermions transforming under the fundamental representation of this new gauge…
General SU(2)xSU(2)xU(1) models represent a well-motivated intermediate step towards the unification of the Standard Model gauge groups. Based on a recent global analysis of low-energy and LEP constraints of these models, we perform…
We consider the extension of the Standard Model with scalar leptoquarks as a portal to dark matter (DM), motivated by the recent anomalies in semi-leptonic $B$-meson decays. Taking singlet and triplet scalar leptoquarks as the best…
In this paper we present an in-depth analysis of a recently proposed Standard Model extension with a complete fourth generation of quarks and leptons, which are vector-like with respect to the Standard Model gauge group and charged under a…
We study extensions of the standard model by one generation of vector-like leptons with non-standard hypercharges, which allow for a sizable modification of the h -> gamma gamma decay rate for new lepton masses in the 300 GeV - 1 TeV range.…
Within the 3-3-1 model framework, we consider the production and decay of fermionic leptoquarks into a striking experimental signature at the LHC: a narrow resonance at the $b$ jet plus same-sign dileptons channel. The data already…
We study the phenomenology of vector resonances in the context of natural composite Higgs models. A mild hierarchy between the fermionic partners and the vector resonances can be expected in these models based on the following arguments.…