  We further study the stochastic model discussed in Ref.[2] in which positive
and negative particles diffuse in an asymmetric, CP invariant way on a ring.
The positive particles hop clockwise, the negative counter-clockwise and
oppositely-charged adjacent particles may swap positions. We extend the
analysis of this model to the case when the densities of the charged particles
are not the same. The mean-field equations describing the model are coupled
nonlinear differential equations that we call the two-component Burgers
equations. We find roundabout weak solutions of these equations. These
solutions are used to describe the properties of the stationary states of the
stochastic model. The values of the currents and of various two-point
correlation functions obtained from Monte-Carlo simulations are compared with
the mean-field results. Like in the case of equal densities, one finds a pure
phase, a mixed phase and a disordered phase.
