Related papers: Single Leptoquark Production
A search for pair-produced leptoquarks is performed using e+e- collision events collected by the OPAL detector at LEP at centre-of-mass energies between 189 and 209 GeV. The data sample corresponds to a total integrated luminosity of 596…
Due to the presence of extra top quark T in the little Higgs models, the $CKM$ matrix is not unitary and the flavor changing neutral currents may exist at the tree level. In the context of the Littlest Higgs(LH) model, we discuss the…
I briefly discuss the search for low mass scalars at Higgs factories as well as available models that render such scalars feasible, where I focus on new developments since the review presented in arXiv:2205.09687 (see also arXiv:2504.11969…
The cross section for vector leptoquark pair production in $e^+e^-$ annihilation is calculated for the case of finite anomalous gauge boson couplings $\kappa_{\gamma, Z}$ and $\lambda_{\gamma, Z}$. The minimal cross section is found to…
The production of massive quarks and leptons in $e^+e^-$ collisions is studied using exact helicity amplitudes. Total cross sections as a function of $y_{\rm cut}$, in both the JADE and the $k_T$ algorithms, are presented and compared with…
The prospects for producing leptoquarks (LQs) in ultrahigh-energy (UHE) neutrino nucleon collisions are re-examined in the light of recent interpretations of HERA data in terms of leptoquark production. We update predictions for…
We study combined leptoquark (LQ) single and pair production at LHC at the level of detector simulation. A set of kinematical cuts has been worked out to maximize significance for combined signal events. It was shown that combination of…
Processes commonly studied at the Large Hadron Collider (LHC) are induced by quarks and gluons inside the protons of the LHC beams. In this letter we demonstrate that, since protons also contain leptons, it is possible to target…
The next generation of $e^+e^-$-colliders will offer a possibility of clean testing of QCD dynamics in the Regge limit. Recent progress in the theoretical description of exclusive processes permits for many of them a consistent use of the…
A sequential fourth generation of quarks and leptons is allowed by precision electroweak constraints if the mass splitting between the heavy quarks is between 50 and 80 GeV. Although heavy quarks can be easily detected at the LHC, it is…
The physics at an e+e- linear collider with a center of mass energy of 3-5 TeV is reviewed. The following topics are covered: experimental environment, Higgs physics, supersymmetry, fermion pair-production, WW scattering, extra dimensions,…
The new colored vector-like heavy fermion $T$ is a crucial prediction in little Higgs models, which plays a key role in breaking the electroweak symmetry. The littlest Higgs model is the most economical one among various little Higgs…
We evaluate the observability of the effects of a scalar singlet leptoquark (LQ) in $\mu$ and $\tau$-pair productions at the $Z$ factory. In the scenario addressing the charged-current anomalies, the LQ contributions to $\mu$-pair final…
The sensitivity of LeHC to different models of "new physics" has been studied, both for the resonance production and in the contact interaction approximation. Expected limits are compared for different running scenarios. Direct leptoquark…
In the framework of the littlest Higgs($LH$) model and the littlest Higgs model with T-parity($LHT$), We investigate the single top production process $e^{-}\gamma\to \nu_{e}b\bar{t}$, and calculate the corrections of these two models to…
We explore the signatures of the $\tilde{R}_2$ class of leptoquark (LQ) models at the proposed $e^- p$ and $e^+p$ colliders. We carry out an analysis for the proposed colliders LHeC and FCC-eh with center of mass (c.m.) energy 1.3 TeV and…
We study single top production at linear lepton colliders with $\sqrt{s} = 0.5$, 1 and 3 TeV. A preliminary analysis shows that despite the large $t\bar t$ background at $\sqrt{s} = 0.5$ and 1 TeV it is possible to obtain a good sensitivity…
In the littlest Higgs model with T-parity, we studied the contributions of the new particles to the top-quark pair production via $e^{+}e^{-}$ collision at the International Linear Collider. We calculated the top-quark pair production cross…
Following the HL-LHC era, proposed lepton colliders highlight the need to study various important Higgs boson production mechanisms to precisely probe the Standard Model Higgs sector. We propose a novel mechanism $e^\pm \gamma \rightarrow…
We study scalar leptoquark production at TESLA and CLIC based e-gamma colliders. Both direct and resolved contributions to the cross section are examined. We find that the masses of scalar leptoquarks can be probed up to about 0.9 TeV at…