Search for Light Gluinos via Decays Containingπ+π−orπ0from a Neutral Hadron Beam at Fermilab

We report on two null searches, one for the spontaneous appearance of ${\pi }^{+}{\pi }^{-}$ pairs, another for a single ${\pi }^0$, consistent with the decay of a long-lived neutral particle into hadrons and an unseen neutral particle. For the lowest level gluon-gluino bound state, known as the $R^0$, we exclude the decays $R^0\to {\pi }^{+}{\pi }^{-}\tilde{\gamma }$ and $R^0\to {\pi }^0\tilde{\gamma }$ for the masses of $R^0$ and $\tilde{\gamma }$ in the theoretically allowed range. In the most interesting $R^0$ mass range, $\le 3\mathrm{GeV}/c^2$, we exclude $R^0$ lifetimes from $3\times {10}^{-10\mathrm{}}\sec$ to as high as ${10}^{-3\mathrm{}}\sec$, assuming perturbative QCD production for the $R^0$.