A supergravity explanation of the CDF $eeγγ$ event

Abstract

We present a unified no-scale supergravity model with a light gravitino that can naturally explain the observed $eeγγ$ event at CDF via right-handed selectron pair-production. The full spectrum of our model can be described in terms of a single parameter and can be distinguished from alternative proposals in the literature. Ongoing and future runs at LEP 2 should be able to probe the full allowed parameter space via acoplanar diphoton events from $e^+e^-\toχ^0_1χ^0_1$ production.