First generation leptoquark search in<i>pp¯</i>collisions at √<i>s</i>=1.8 TeV

Abstract

We report on a search for first generation leptoquarks with the DO/ detector at the Fermilab Tevatron pp\ifmmode\bar\else\textasciimacron\fi{} collider at \ensuremath{\surd}s =1.8 TeV. This search is based on 15 ${\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$ of data. Leptoquarks are assumed to be produced in pairs and to decay into an electron + quark with branching ratio \ensuremath{\beta}. No leptoquark candidates were found. We obtain cross section times branching ratio limits as a function of leptoquark mass. For pair production of scalar leptoquarks, we set a leptoquark mass limit of 133 GeV for \ensuremath{\beta}=1 and 120 GeV for \ensuremath{\beta}=0.5 at 95% confidence level.