Searches for prompt light gravitino signatures in e+e- collisions at √s = 189 GeV

Searches for final states expected in models with light gravitinos have been performed, including exptl. topologies with multi-leptons with missing energy, leptons and photons with missing energy, and jets and photons with missing energy. No excess over the expectations from the Std. Model has been obsd. Limits are placed on prodn. cross-sections in the different exptl. topologies. Addnl., combining with searches for the anomalous prodn. of lepton and photon pairs with missing energy, results are interpreted in the context of minimal models of gauge mediated SUSY breaking. Exclusion limits at the 95% confidence level on the supersym. particle masses of ml~> 83 GeV and mc~10> 85 GeV for tanb=2, and mt~> 69 GeV, me~,m~> 88 GeV and mc~10> 76 GeV for tanb=20, are established. [on SciFinder (R)]