Search for pair production of second generation scalar leptoquarks

We report on a search for the pair production of second generation scalar leptoquarks (LQ  ) in pp¯ collisions at the center of mass energy s=1.96 TeV using a data set corresponding to an integrated luminosity of 1.0 fb−11.0 fb−1 collected with the DØ experiment at the Fermilab Tevatron Collider. Topologies arising from the LQLQ¯→μqνq and LQLQ¯→μqμq decay modes are investigated. No excess of data over the standard model prediction is observed and upper limits on the leptoquark pair production cross section are derived at the 95% C.L. as a function of the leptoquark mass and the branching fraction β   for the decay LQ→μqLQ→μq. These are interpreted as lower limits on the leptoquark mass as a function of β  . For β=1(0.5), scalar second generation leptoquarks with masses up to 316 GeV (270 GeV) are excluded.