J. C. Zarnecki
X-ray studies of the Puppis-A supernova remnant
1977 (supervisor: J. L. Culhane)

This thesis primarily describes a Skylark sounding rocket experiment, using a Bragg crystal spectrometer, to search for X-ray line emission from the supernova remnant, Puppis-A. The results of this experiment are presented and are believed to represent the first high resolution detection of X-ray line emission (O VIII Ly-alpha) from a cosmic X-ray source. The implications of this result, in terms of the physical parameters of the source, are investigated.

In addition, proportional counter data from the Copernicus and Ariel V satellites are described and interpreted. The Ariel V data represent the first spectral observations of Puppis-A at energies above 2 keV, a region where spectral analysis is considerably easier due to the likely absence of strong emission lines over the temperature range 1 - 10 x 10^6 K. These data are combined to produce an overall picture of the X-ray emission from Puppis-A, and this interpretation is reviewed in the context of the data of other observers. In particular, it is shown that it is necessary to invoke a model involving plasma at two distinct temperatures, and an attempt is made to estimate the relative spatial positions of these two components. This interpretation is believed to resolve the discrepancies arising from the spectral analyses of earlier observers.

The radio and optical observations of this source are reviewed, with particular emphasis on the optical coronal line emission. Attempted observations of the coronal lines are used to place limitations on the derived source model. Reasons for the development of two distinct temperatures are investigated and this is interpreted in terms of the interaction of the supernova shock wave with a dense interstellar cloud.