Search for Gluinos and Squarks Using Like-Sign Dileptons in pp¯ Collisions at s=1.8 TeV

We present results of the first search for like-sign dilepton ( $e^{\pm }{e}^{\pm }$, $e^{\pm }{\mu }^{\pm }$, ${\mu }^{\pm }{\mu }^{\pm }$) events associated with multijets and large missing energy using $106{\mathrm{pb}}^{-1\mathrm{}}$ of data in $p\overline{p}$ collisions at $\sqrt{s}=1.8\mathrm{}\mathrm{TeV}$ collected during 1992–1995 by the CDF experiment. Finding no events that pass our selection, we examine pair production of gluinos ( $\tilde{g}$) and squarks ( $\tilde{q}$) in a constrained framework of the minimal supersymmetric standard model. At $\tan \beta =2\mathrm{}$ and $\mu =-800\mathrm{}\mathrm{GeV}{/c}^2$, we set $95\%$ confidence level limits of $M_{\tilde{g}}>221\mathrm{}\mathrm{GeV}{/c}^2$ for $M_{\tilde{g}}\simeq M_{\tilde{q}}$, and $M_{\tilde{g}}>168\mathrm{}\mathrm{GeV}{/c}^2$ for $M_{\tilde{q}}\gg M_{\tilde{g}}$, both with small variation as a function of $\mu$.