Search for first generation scalar leptoquark pairs in pp̄ collisions at √s = 1.8 TeV

We have searched for first generation scalar leptoquark (LQ) pairs in the eν+jets channel using pp collider data (∫Ldt≈115 pb -1 ) collected by the D0 experiment at the Fermilab Tevatron during 1992-1996. The analysis yields no candidate events. We combine the results with those from the ee+jets and νν+jets channels to obtain 95% confidence level (C.L.) upper limits on the LQ pair production cross section as a function of mass and of β, the branching fraction to a charged lepton. Comparing with the next-to-leading order theory, we set 95% C.L. lower limits on the LQ mass of 225, 204, and 79 GeV/c 2 for β = 1, ½, and 0, respectively.