We consider a nonautonomous transport problem, the modelization of the char
ge exchange dynamics in a monoatomic ionized gas, and apply scattering theo
ry to its dynamics. The free dynamics corresponds to the evolution of the t
otal distribution of particles (neutral plus ionized particles) and the per
turbed dynamics corresponds to the evolution of the neutral particles, whic
h is the solution of a nonautonomous transport problem. The existence of th
e time-dependent wave operators was proved by the first author. In the pres
ent paper we follow Howland's formalism in constructing a stationary scatte
ring theory for this nonautonomous transport problem by studying the evolut
ion equation. We prove the existence of the wave operators and by using the
smooth perturbation technique we obtain the similarity between perturbed a
nd unperturbed operators.