Search for Leptoquarks in Electron-Photon Scattering at sqrt(s_ee) up to 209 GeV at LEP

TL;DR

This paper reports on a search for leptoquarks and squarks in electron-photon scattering at LEP energies, finding no evidence of new particles and setting limits on their couplings.

Contribution

It provides the first limits on leptoquark couplings in electron-photon scattering at LEP energies, expanding the search for new physics beyond previous experiments.

Findings

No excess events observed over Standard Model background

Limits set on leptoquark couplings for various branching ratios

Constraints placed on squark production in R-parity violating SUSY

Abstract

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 OPAL detector at LEP at e+e- centre-of-mass energies between 189 and 209 GeV. No excess of events is found over the expectation from Standard Model background processes. Limits are computed on the leptoquark couplings for different values of the branching ratio to electron-quark final states.