Search for first-generation scalar leptoquarks inpp¯collisions ats=1.96 TeV

We report on a search for pair production of first-generation scalar leptoquarks (LQ) in pp collisions at {radical}(s)=1.96 TeV using an integrated luminosity of 252 pb{sup -1} collected at the Fermilab Tevatron collider by the D0 detector. We observe no evidence for LQ production in the topologies arising from LQLQ{yields}eqeq and LQLQ{yields}eq{nu}q, and derive 95% C.L. lower limits on the LQ mass as a function of {beta}, where {beta} is the branching fraction for LQ{yields}eq. The limits are 241 and 218 GeV/c{sup 2} for {beta}=1 and 0.5, respectively. These results are combined with those obtained by D0 at {radical}(s)=1.8 TeV, which increases these LQ mass limits to 256 and 234 GeV/c{sup 2}.