VARIATIONS ON MINIMAL GAUGE-MEDIATED SUPERSYMMETRY BREAKING

We study various modifications to the minimal models of gauge-mediated supersymmetry breaking. We argue that, under reasonable assumptions, the structure of the messenger sector is rather restricted. We investi gate the effects of possible mixing between messenger and ordinary squ ark and slepton fields and, in particular, violation df universality. We show that acceptable values for the mu and B parameters can natural ly arise from discrete, possibly horizontal, symmetries. We claim that in models where the supersymmetry-breaking parameters A and B vanish at the tree level, tan beta could be large without fine-tuning. We exp lain how the supersymmetric CP problem is solved in such models.