Search for Light Supersymmetric Baryons

We have searched for the production and decay of light supersymmetric baryons produced in $800\mathrm{GeV}/c$ proton copper interactions in a charged hyperon beam experiment. We observe no evidence for the decays $R^{+}\left(\mathrm{uud}\tilde{g}\right)\to S^0\left(\mathrm{uds}\tilde{g}\right){\pi }^{+}$ and $X^{-}\left(\mathrm{ssd}\tilde{g}\right)\to S^0\left(\mathrm{uds}\tilde{g}\right){\pi }^{-}$ in the parent mass and lifetime ranges of $1700–2500\mathrm{MeV}{/c}^2$ and 50–500 ps. Production upper limits for $R^{+}$ at $x_F=0.47\mathrm{}$, $P_t=1.4\mathrm{}\mathrm{GeV}{/c}^2$ and $X^{-}$ at $x_F=0.48\mathrm{}$, $P_t=0.65\mathrm{}\mathrm{GeV}{/c}^2$ of less than ${10}^{-3\mathrm{}}$ of all charged secondary particles produced are obtained for all but the highest masses and shortest lifetimes predicted.