Abstract :
We present a simple model of gauge mediated supersymmetry breaking with composite messenger fields. Our model is based on the gauge group SP(8)×SU(2). By the strong SP(8) dynamics, supersymmetry is dynamically broken and the composite fields with charges under the standard model gauge group appear at low energy. The U(1)R symmetry breaking mass terms for the composite fields are generated by the strong SU(2) dynamics. Then, the composite fields play a role of the messenger fields. On the other hand, the theoretical bounds on the parameters in our model are discussed. Especially, the lower bound on the dynamical scale of the SP(8)×SU(2) gauge interaction is roughly 1015 GeV.