1 99 6 Novel Quenched Disorder Fixed Point in a Two - Temperature Lattice Gas

We investigate the effects of quenched randomness on the universal properties of a two-temperature lattice gas. The disorder modifies the dynamical transition rates of the system in an anisotropic fashion, giving rise to a new fixed point. We determine the associated scaling form of the structure factor, quoting critical exponents to two-loop order in an expansion around the upper critical dimension d c = 7. The close relationship with another quenched disorder fixed point, discovered recently in this model, is discussed.