title: Critical behavior of a nonequilibrium system with two nonordering conserved fields.
abstract: We investigate the critical behavior of a nonequilibrium system with two particle species A and B that exhibits a continuous absorbing-state phase transition. The number of particles of each species (N(A) and N(B)) is conserved by the dynamical process. Numerical results show that the order parameter exponent beta depends on the ratio N(B)/N(A) at criticality. Some aspects of critical dynamic behavior are also studied, namely, the decay of the active density at criticality and the critical spreading of a perturbation to an absorbing configuration. Anomalies in the relaxation are associated with the presence of different time scales in the dynamics of the model.
authors.affiliation: Departamento de Física and Centro de Física do Porto, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal. mcmarq@fc.up.pt
authors.forename: M C
authors.initials: MC
authors.lastname: Marques