  The evolution of type Ia supernova binary system progenitors is highly
uncertain. Several evolutionary models predict that the accretion of mass onto
the white dwarf is accompanied by mass ejection from the binary in the form of
a powerful wind, but very few observations have been made during the initial
phase of formation of supernovae remnants, when the interaction of supernova
ejecta with presupernova wind could be tested. Here we present hydrodynamical
simulations of supernova ejecta interaction with an ambient medium modified by
presupernova wind. The structure of the ambient medium when the supernova
explodes is very sensitive to the details of wind history, and the evolution of
the supernova remnant can be affected during several thousand years. We have
found that the forward shock expansion parameter is a good tool for
discriminating between several wind models. The evolution of the supernova
remnant in the presence of an ambient medium modified by interaction with
pre-supernova wind cannot be described by a similarity solution. We also rule
out simple models based on a circumstellar medium that merges smoothly with a
uniform density ambient medium.

Astrophysics