Critical time for shock formation in radiative magnetogasdynamics

For the general case of magnetogasdynamics coupled to the radiation field, a differential scheme which is capable of dealing with variable optical depths, leads to a hyperbolic system of equations. To this system the standard techniques for evaluating the critical time of weak discontinuities is applied. In this paper the critical time for radiative magnetoacoustic waves propagating into a constant state is analyzed. Plane waves, spherical waves and cylindrical waves are studied.