Related papers: Exploring leptoquark effects in hyperon and kaon d…
If electroweak symmetry breaking arises via strongly-coupled physics, the observed suppression of flavour-changing processes suggests that fermion masses should arise via mixing of elementary fermions with composite fermions of the strong…
We perform a model independent analysis so as to constrain the leptoquark (LQ) models from negative searches for $\mu \to e \gamma$, $\mu \to 3e$ decays (and analogous processes in the $\tau$ sector), and coherent $\mu-e$ conversion in…
In the case where the Standard Model is extended by one heavy Majorana fermion, the branching fractions of semileptonic meson decays into same-sign and opposite-sign dileptons are expected to be of the same order. As we discuss here, this…
It is assumed that neutrino-nucleon scattering at ultra-high energies effectively proceeds through excitations of leptoquarks in neutrino-quark subprocesses. This approach reproduces the behavior of the energy dependence of the ultra-high…
The measured branching fractions of $B$-mesons into leptonic final states derived by the LHCb collaboration hint towards the breakdown of lepton flavour universality. In this work we take at face value the so-called $R_{D^{(*)}}$…
Leptoquarks arise naturally in models attempting the unification of the quark and lepton sectors of the standard model of particle physics. Such particles could be produced in the interaction of high energy quasi-horizontal cosmic neutrinos…
We show that a model with a scalar leptoquark of hypercharge $Y=1/6$ which includes the light right-handed neutrinos, can successfully describe both of the $B$-physics anomalies, $R_K^{\rm exp} < R_K^{\rm SM}$ and $R_D^{\rm exp} > R_D^{\rm…
That massless dark photons could exist and have flavor-changing magnetic-dipole interactions with down-type light quarks is an attractive possibility which may be realized in various new-physics scenarios. It is potentially testable not…
We study methods of extracting new physics signals in final states with a top-quark pair plus large missing energy at the LHC. We consider two typical examples of such new physics: pair production of a fermionic top partner (a $T'$ in…
The measurements of hadron and lepton-pair production cross sections and leptonic forward-backward asymmetries performed with the L3 detector at centre-of-mass energies between 130 GeV and 189 GeV are used to search for new physics…
Current LHC searches for non-supersymmetric singly-charged scalars, based on Two-Higgs-Doublet models, in general focus the analysis on third-generation fermions in the final state. However, singly-charged scalars in alternative extensions…
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…
Purely leptonic $B$ meson decays provide unique probes for physics Beyond the Standard Model. We study the impact of a scalar leptoquark, $S_1$, on $B \to \mu \bar\nu$ decay. We find that, for $m_{S_1}\sim 1$ TeV, the $S_1$ leptoquark can…
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…
This article describes the search for pair production of scalar leptoquarks performed by the CMS collaboration using the data from the 2010 proton-proton run of the Large Hadron Collider at a center of mass energy of 7 TeV. The following…
We present the cross section for pair production of scalar leptoquarks $LQ$ in $p\bar{p}$ collisions, $p+\bar{p} \to LQ + \bar{LQ} + X$, at the Fermilab Tevatron in next-to-leading order QCD. Including the higher-order corrections…
Leptoquarks are theorized particles of either scalar or vector nature that couple simultaneously to quarks and leptons. Motivated by recent measurements of coherent elastic neutrino-nucleus scattering, we consider the impact of scalar…
We investigate the impact of higher-dimensional operators on low-scale leptogenesis (LG) via oscillations of right-handed neutrinos within the neutrino-extended Standard Model Effective Field Theory ($\nu$SMEFT) and discuss the connection…
We study the influence of leptophilic dark matter interactions on decays of muons and ground state mesons in existing experiments. We consider a secluded dark sector exclusively interacting with leptons via either a (leptophilic) scalar or…
One of the fundamental predictions of the Standard Model is Lepton Flavour Universality. Any deviation from this prediction would indicate the existence of physics beyond the Standard Model. Recent LHCb measurements present a pattern of…