X-Ray emission from SN 2004dj: A Tale of Two Shocks

Type IIP (Plateau) Supernovae are the most commonly observed variety of core collapse events. They have been detected in a wide range of wavelengths from radio, through optical to X-rays. The standard picture of a type IIP supernova has the blastwave interacting with the progenitor's circumstellar matter to produce a hot region bounded by a forward and a reverse shock. This region is thought to be responsible for most of the X-ray and radio emission from these objects. Yet the origin of X-rays from these supernovae is not well understood. We shall talk about how multiwavelength observations can be used to determine the pre-explosion mass loss rate, blastwave velocity, electron acceleration and magnetic field amplification efficiencies. This will answer some open questions, while raising some new ones.