Shadows of our Former Companions: How the Single-Degenerate Binary Type   Ia Supernova Scenario Affects Remnants
  Here we present three-dimensional high resolution simulations of Type Ia supernova in the presence of a non-degenerate companion. We find that the presence of a nearby companion leaves a long-lived hole in the supernova ejecta. In particular, we aim to study the long term evolution of this hole as the supernova ejecta interacts with the surrounding interstellar medium. Using estimates for the x-ray emission, we find that the hole generated by the companion remains for many centuries after the interaction between the ejecta and the interstellar medium. We also show that the hole is discernible over a wide range of viewing angles and companion masses. 
William J Gray, Cody Raskin, and J. Michael Owen
astro-ph.HE