Search for First Generation Leptoquark Pair Production inpp¯Collisions ats}=1.8TeV

We present the results of a search for first generation scalar leptoquarks pairs $\left(S_1{\overline{S}}_1\right)$ in $110\pm 7\mathrm{pb}{}^{-1\mathrm{}}$ of data collected by the Collider Detector at Fermilab. We assume both leptoquarks decay to an electron and a quark. Three candidate events, with masses below $140\mathrm{GeV}{/c}^2$ and consistent with background expectations, are observed. We obtain a 95% confidence level upper limit on the production cross section as a function of the leptoquark mass. Using a next-to-leading order calculation of $S_1{\overline{S}}_1$ production, we exclude scalar leptoquarks with mass less than $213\mathrm{GeV}{/c}^2$ at 95% C.L. for a branching ratio into $\mathrm{eq}$ equal to 1.