Search for Chargino-Neutralino Production inpp¯Collisions at√s=1.8TeV

We have searched for chargino-neutralino production $\left({\tilde{\chi }}_1^{\pm }{\tilde{\chi }}_2^0\right)$ in 1.8 TeV $p\overline{p}$ collisions, followed by their leptonic decays ${\tilde{\chi }}_1^{\pm }\to {\tilde{\chi }}_1^0{\ell }^{\pm }\nu$ and ${\tilde{\chi }}_2^0\to {\tilde{\chi }}_1^0{\ell }^{+}{\ell }^{-}$. These trilepton events are expected within a framework of the minimal supersymmetric standard model (MSSM). In a $19.1{\mathrm{pb}}^{-1\mathrm{}}$ data sample collected with a Collider Detector at Fermilab, no trilepton events were observed. Upper limits on $\sigma (p\overline{p}\to {\tilde{\chi }}_1^{\pm }{\tilde{\chi }}_2^0)̇\mathrm{BR}({\tilde{\chi }}_1^{\pm }{\tilde{\chi }}_2^0\to 3\ell +X)$ were obtained for various MSSM parameter space regions, yielding new 95% confidence level lower limits for the neutralino $\left({\tilde{\chi }}_2^0\right)$ mass which extend as high as $49\mathrm{GeV}{/c}^2$.