AN IMPROVED MODEL OF DIRECT GAUGE MEDIATION

We present a new, improved model of gauge mediation of dynamical SUSY Breaking: the model does not have gauge messengers or similar to 10 Te V scalars charged under the Standard Model (SM), thus avoiding the pro blem of negative (mass)(2) for supersymmetric SM (SSM) scalars faced b y some earlier models. The gauge mediation is direct, i.e., the messen gers which communicate SUSY breaking to the SSM fields carry quantum n umbers of the gauge group which breaks SUSY. These messenger fields co uple to a modulus field. The model has a very simple particle content: the modulus and the messengers are the only chiral superfields (other than the SSM fields) in the model. The inverted hierarchy mechanism i s used to generate a local SUSY breaking minimum for the modulus field in a perturbative regime thus making the model calculable. (C) 1998 P ublished by Elsevier Science B.V. All rights reserved.