Cosmological Magnetic Fields from Gauge-Mediated Supersymmetry-Breaking Models

We study the generation of primordial magnetic fields, coherent over cosmologically interesting scales, by cosmological creation of charged scalar particles during the reheating period. We show that magnetic fields consistent with those detected by observation may obtained if the particle mean life mechanism to minimal gauge mediated supersymmetry-breaking models, in the case in which the lightest stau \tilde\tau_1 is the next-to-lightest supersymmetric particle. We show that, for a large range of phenomenologically acceptable values of the supersymmetry-breaking scale \sqrt{F}, the generated primordial magnetic field can be strong enough to seed the galactic dynamo.