Search for Scalar Leptoquark Pairs Decaying to $\nu \bar \nu q \bar q$   in \ppbar Collisions at $\sqrt {s} = 1.96$ TeV
  We report on a search for the pair production of scalar leptoquarks, $LQ$, using 191 pb$^{-1}$ of proton-antiproton collision data recorded by the CDF experiment during Run II of the Tevatron. The leptoquarks are sought via their decay into a neutrino and quark yielding missing transverse energy and several jets of large transverse energy. No evidence for leptoquark production is observed, and limits are set on $\sigma(p\bar p\to LQ\bar{LQ} X \to \nu\bar\nu q\bar q X)$. Using a next-to-leading order theoretical prediction of the cross section for scalar leptoquark production, we exclude first-generation leptoquarks in the mass interval 78 to 117 GeV$/c^2$ at the 95% confidence level for BR($LQ\to \nu q)=100%$. 
CDF Collaboration: D. Acosta, et al