2004MNRAS.354L..13K

We present results from the first high-resolution, high signal-to-noise ratio spectrum of SN 2002ic. The resolved Hα line has a P Cygni-type profile, clearly demonstrating the presence of a dense, slow-moving (∼100 km/s) outflow. We have additionally found a huge near-infrared excess, hitherto unseen in Type Ia supernovae. We argue that this is due to an infrared light-echo arising from the pre-existing dusty circumstellar medium. We deduce a circumstellar medium mass probably exceeding 0.3 M_☉produced by a mass-loss rate greater than several times 10^–4 M_☉/yr. For the progenitor, we favour a single-degenerate system where the companion is a post-asymptotic giant branch star. As a by-product of our optical data, we are able to provide a firm identification of the host galaxy of SN 2002ic.