Light-Gravitino Production at Hadron Colliders

We consider the production of gravitinos ($\tilde{G}$) in association with gluinos ($\tilde{g}$) or squarks ($\tilde{q}$) at hadron colliders, including the three main sub-processes: $q\bar{q}->\tilde{g}\tilde{G}$, $qg -> \tilde q\widetilde G$,and$gg -> \tilde g\widetilde G$. These channels become enhanced to the point of being observable for sufficiently light gravitino masses ($m_{\tilde{G}}<{10}^{-4}eV$), as motivated by some supersymmetric explanations of the CDF $ee\gamma \gamma +E_{T,miss}$ event. The characteristic signal of such events would be monojets, as opposed to dijets obtained in the more traditional supersymmetric process $p\bar{p}->\tilde{g}\tilde{g}$. Searches for such events at the Tevatron can impose lower limits on the gravitino mass. In the Appendix, we provide a complete set of Feynman rules for gravitino interactions used in our calculation.