Search for Diphoton Events with Large Missing Transverse Energy inpp¯Collisions at=1.8TeV

A search for new physics has been carried out in the channel $p\overline{p}\to \gamma \gamma +E_T$, as expected in various supersymmetric models. We require two photons with transverse energy $E_T^{\gamma }>12\mathrm{}\mathrm{GeV}$ and pseudorapidity $|{\eta }^{\gamma }|<1.1\mathrm{}$. The distribution of missing transverse energy ( $E_T$) is consistent with background and no events have $E_T>25\mathrm{}\mathrm{GeV}$. We set limits on production cross sections for selectron, sneutrino, and neutralino pairs, decaying into photons, which range from about 400 fb to 1 pb depending on the sparticle masses. A general limit of 185 fb (95% C.L.) is set on $\sigma (p\overline{p}\to \gamma \gamma E_T+X)$, where $E_T^{\gamma }>12\mathrm{}\mathrm{GeV}$, $|{\eta }^{\gamma }|<1.1\mathrm{}$, and $E_T>25\mathrm{}\mathrm{GeV}$.