Search for First Generation Scalar Leptoquark Pairs in ppbar Collisions at sqrt(s)=1.8 TeV

TL;DR

This study searches for first-generation scalar leptoquark pairs in proton-antiproton collisions at 1.8 TeV, setting mass limits based on non-observation in multiple decay channels using Fermilab Tevatron data.

Contribution

It provides the first combined limits on scalar leptoquark masses across different decay channels using Tevatron data, improving constraints on their existence.

Findings

No candidate events observed in the search.

Set lower mass limits of 225, 204, and 79 GeV/c^2 for different branching ratios.

Combined results improve previous constraints on scalar leptoquarks.

Abstract

We have searched for first generation scalar leptoquark (LQ) pairs in the enu+jets channel using ppbar collider data (integrated luminosity= 115 pb^-1) collected by the DZero experiment at the Fermilab Tevatron during 1992-96. The analysis yields no candidate events. We combine the results with those from the ee+jets and nunu+jets channels to obtain 95% confidence level (CL) upper limits on the LQ pair production cross section as a function of mass and of beta, the branching fraction to a charged lepton. Comparing with the next-to-leading order theory, we set 95% CL lower limits on the LQ mass of 225, 204, and 79 GeV/c^2 for beta=1, 1/2, and 0, respectively.