Using a sample of e + e − annihilation events collected at the Z resonance corresponding to an integrated luminosity of 11.2 pb −1 , we have searched for γX final states where X represents stable, weakly interacting particles and the energy of the photon is greater than 1 2 E beam . No events were found. The results have been interpreted within a composite Z model and a supergravity model with a light gravitino.