Related papers: Bounds on Vector Leptoquarks
We make a comprehensive study of indirect bounds on scalar leptoquarks that couple chirally and diagonally to the first generation by examining available data from low energy experiments as well as from high energy e+ e- and p pbar…
The vertex corrections to the leptonic partial widths of the $Z$ induced by leptoquarks that couple leptons to the top quark are considered. We obtain stringent bounds on the parameter space of the masses and Yukawa couplings of these…
We analyse the constraints on scalar leptoquarks coming from radiative corrections to $Z$ physics. We perform a global fitting to the LEP data including the contributions of the most general effective Lagrangian for scalar leptoquarks,…
A summary is given on the experimental bounds for the couplings and masses of scalar and vector leptoquarks associated to the first fermion generation. We investigate to which extent an interpretation of the recently reported excess of…
We obtain the constraints on scalar leptoquarks coming from radiative corrections to $Z$ physics. We perform a global fitting to the LEP data including the contributions of the most general effective Lagrangian for scalar leptoquarks, which…
A search for scalar and vector leptoquarks coupling to first generation fermions is performed using the e^+p and e^-p scattering data collected by the H1 experiment between 1994 and 2000. The data correspond to a total integrated luminosity…
A search for first generation scalar and vector leptoquarks produced in ep collisions is performed by the H1 experiment at HERA. The full H1 data sample is used in the analysis, corresponding to an integrated luminosity of 446 pb^-1. No…
The Standard Model is extended by a SU(2)L singlet of vector leptoquarks. An additional SU(4) gauge symmetry between right-handed up quarks and right-handed leptons is introduced to render the model renormalizable. The arrangement is made…
Data from HERA, LEP and the Tevatron, as well as from low energy experiments are used to constrain the Yukawa couplings for scalar and vector leptoquarks in the Buchmuller-Ruckl-Wyler effective model. In the limit of very high leptoquark…
A search for first generation scalar and vector leptoquarks produced in ep collisions is performed by the H1 Collaboration at HERA. The full H1 data sample is used in the analysis, corresponding to an integrated luminosity 446 pb^-1. No…
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…
I discuss the production of leptoquarks in $p\bar{p}$ collisions at the Fermilab Tevatron. Evaluated on the basis of a recent next-to-leading order calculation, the combined D0 and CDF leptoquark searches lead to a parameter-free lower mass…
We derive new bounds on scalar leptoquark couplings from K^0 K^0 bar, D^0 D^0 bar and B^0 B^0 bar mixing. Although leptoquarks contribute to these processes only at one loop, their contribution is large, due to the lack of GIM cancelation.…
In this article we perform a combined analysis of low energy precision constraints and LHC searches for leptoquarks which couple to first generation fermions. Considering all ten leptoquark representations, five scalar and five vector ones,…
We examine the phenomenological implications of a 200 GeV leptoquark in light of the recent excess of events at HERA. Given the relative predictions of events rates in e^+p versus e^-p, we demonstrate that classes of leptoquarks may be…
A search for scalar and vector leptoquarks coupling to first generation fermions is performed in the H1 experiment at the ep collider HERA. The analysis uses e^- p data collected in 1998 and 1999 at a centre-of-mass energy of 320 GeV,…
Leptoquark searches are considered for future experiments at HERA, Tevatron, LHC, TESLA and THERA. Expected exclusion limits from direct leptoquark searches (leptoquark pair production and single leptoquark production) are compared with…
We investigate the discovery potential for first generation leptoquarks at the LEP and LEP200 $e^+e^-$ colliders. We consider single leptoquark production via resolved photon contributions which offers a much higher kinematic limit than the…
Searches for first generation scalar and vector leptoquarks, and for squarks in R-parity violating SUSY models with the direct decay of the squark into Standard Model particles, have been performed using e+e- collisions collected with the…
A search for leptoquarks at HERA was performed in H1 using 1994 $e^+ p$ data corresponding to an integrated luminosity of about $3 \pb^{-1}$. Single leptoquarks were searched for in direct positron-quark fusion processes taking into account…