Search for Chargino-Neutralino Associated Production at the Fermilab Tevatron Collider

We have searched in $p\overline{p}$ collisions at $\sqrt{s}=1.8\mathrm{}\mathrm{TeV}$ for events with three charged leptons and missing transverse energy. In the minimal supersymmetric standard model, we expect trilepton events from chargino-neutralino $\left({\tilde{\chi }}_1^{\pm }{\tilde{\chi }}_2^0\right)$ pair production, with subsequent decay into leptons. We observe no candidate $e^{+}{e}^{-}{e}^{\pm }$, $e^{+}{e}^{-}{\mu }^{\pm }$, $e^{\pm }{\mu }^{+}{\mu }^{-}$, or ${\mu }^{+}{\mu }^{-}{\mu }^{\pm }$ events in $106{\mathrm{pb}}^{-1\mathrm{}}$ integrated luminosity. We present limits on the sum of the branching ratios times cross section for the four channels: ${\sigma }_{{\tilde{\chi }}_1^{\pm }{\tilde{\chi }}_2^0}B({\tilde{\chi }}_1^{\pm }{\tilde{\chi }}_2^0\to 3\ell +X)<0.34\mathrm{}\mathrm{pb}$, $M_{{\tilde{\chi }}_1^{\pm }}>81.5\mathrm{}\mathrm{GeV}{/c}^2$, and $M_{{\tilde{\chi }}_2^0}>82.2\mathrm{GeV}{/c}^2$ for $\tan \beta =2\mathrm{}$, $\mu =-600\mathrm{GeV}{/c}^2$, and $M_{\tilde{q}}{=M}_{\tilde{g}}$.