Related papers: Fresh look at the LHC limits on vector leptoquarks
Leptoquarks (LQ) with couplings to the third generation of Standard Model (SM) quarks have been proposed as possible explanations of the flavour anomalies indicating the violation of lepton flavour universality (LFV). The CMS collaboration…
We investigate the discovery potential for first generation leptoquarks at the LEP200 $e^+e^-$ collider. We consider direct leptoquark searches using single leptoquark production via resolved photon contributions which offers a much higher…
Leptoquarks (LQ) are predicted by many new physics theories to describe the similarities between the lepton and quark sectors of the Standard Model and offer an attractive potential explanation for the lepton flavour anomalies observed at…
We analyse for the first time the CP violating ratio $\varepsilon'/\varepsilon$ in $K\to \pi\pi$ decays in leptoquark (LQ) models. Assuming a mass gap to the electroweak (EW) scale, the main mechanism for LQs to contribute to…
A search for pair-produced scalar and vector leptoquarks decaying into quarks and leptons of different generations is presented. It uses the full LHC Run 2 (2015-2018) data set of 139 fb$^{-1}$ collected with the ATLAS detector in…
We introduce the leptoquark (LQ) toolkit, TooLQit, which includes leading-order FeynRules models for all types of LQs and a Python-based calculator, named CaLQ, to test if a set of parameter points are allowed by the LHC dilepton searches.…
Vectorlike fermions are an important target for hadron collider searches. We show that the vectorlike quarks may predominantly decay via higher-dimensional operators into a quark plus a couple of other Standard Model fermions. Pair…
New vector-like quarks can have sizable couplings to first generation quarks without conflicting with current experimental constraints. The coupling with valence quarks and unique kinematics make single production the optimal discovery…
A comprehensive extension of the ordinary 2-Higgs Doublet Model (2HDM), supplemented by Vector-Like Quarks (VLQs), in the "alignment limit" is presented. In such a scenario, we study the possibility that Large Hadron Collider (LHC) searches…
Vector-like quarks (VLQs) that are partners of the heavy top and bottom quarks are predicted in many extensions of the Standard Model (SM). We explore the possibility that these states could explain not only the longstanding anomaly in the…
We study contributions of single scalar or vector leptoquark (LQ) to loop-induced Higgs processes, gluon fusion production ($g g \to h$) and $h \to \gamma \gamma$ decay, by analyzing the current Higgs data from the LHC Run I and II. Scalar…
We present a detailed numerical study of lepton-pair production via the Drell-Yan process above the Z-peak at the LHC. Our results consistently combine next-to-next-to-leading order QCD corrections and next-to-leading order electroweak…
Scalar leptoquarks (sLQs) appear in a wide range of ultraviolet-motivated extensions of the Standard Model and provide a natural link between the quark and lepton sectors. In this work, we investigate the discovery potential of an sLQ…
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 $G_{SM}' = G_{SM} \times…
Pair production of new vector-like quarks in pp collisions is considered model independent as it is usually dominated by QCD production. We discuss the interpretation of vector-like quark searches in the case that QCD is not the only…
We derive bounds on vector leptoquarks coupling to the first generation, using data from low energy experiments as well as from high energy accelerators. Similarly to the case of scalar leptoquarks, we find that the strongest indirect…
Existences of vector-like quarks (VLQs) are predicted in many new physics scenarios beyond the Standard Model (SM). We study the possibility of detecting the vector-like bottom quark (VLQ-$B$) being the $SU(2)$ singlet with electric charge…
We present model independent constraints on the masses and couplings to fermions of $B$ and $L$ conserving leptoquarks. Such vector or scalar particles could have masses below 100 GeV and be produced at HERA; we list the generation…
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.…
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…