Testing gauge-gravitino coupling in gauge-mediated supersymmetry breaking through single photon events

We show that the process e+e−→γ+ missing energy, arising from the pair production of neutralinos, can probe the γ−γ̃−G̃ as well as the Z−Z̃−G̃ couplings in Gauge Mediated Supersymmetry Breaking models. This enables one to study the mutual relationship of the Goldstino couplings of the different gauginos, a feature whose testability has not been emphasized so far. The Standard Model backgrounds get suppresed with the use of a right polarized electron beam. The energy and angular distribution of the emitted photon can distinguish such models from the minimal supersymmetric theory and its variants.