Probing the Environments of Young Supernovae with XMM-Newton

By observing the Xray emission properties of young supernovae (SNe), physicalkey parameters such as the circumstellar matter (CSM) density, the masslossrate of the progenitor, and the temperature of the outgoing and reverse shockcan be studied as a function of time. We propose followup observations of thebrightest known Xray emitting SNe (1978K, 1979C, 2004dj) to study thetemperature evolution, establish the physical parameters of the ambient CSM outto radii of E18cm from the sites of the explosions, and to monitor the masslossrates over 10^4 years in the progenitors stellar wind history. Studying thesekey parameters as a function of time has never been done before. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]