Dynamics of radiative supernova remnants

The authors study the evolution of a supernova remnant (SNR) evolving in a homogeneous, uniform medium. They have concentrated on the transition from the adiabatic stage to the radiative pressure-driven snowplow stage, and the possible further establishment of a momentum-conserving snowplow stage. In the numerically simulated example (ejecta mass of 3 M_sun;, ambient hydrogen density of 0.1 cm⁻³), the radiative stage begins after less than one sound crossing time from the end of the free-expansion stage, and as a result the interior of the blast wave never completely settles to the Sedov-Taylor similarity solution. The authors also provide a simple physical model for the overall dynamics and present analytic approximations, good to a few percent in radius and velocity when compared with the numerical simulations.