HB21 and W63: Two Aged Supenova Remnants with Clumpy X-ray Morphologies

This was a grant to analyze ROSAT PSPC data on two large diameter, low surface brightness galactic SNRs - HB21 and W63. Both have limb-brightened radio morphologies and X-ray emission which can be characterized as coming from localized regions from the "interior" of the SNRS. The Einstein observations were of these SNRs were very incomplete. The goals of the observations were to obtain much better X-ray maps of the SNRS, to determine the spectral characteristics of the X-ray emission, and to attempt to understand the conditions of the ISM which leads to the morphologies of the SNRS.