F. J. Hawkins
A study of binary mask optics and telescope systems for X-ray astronomy
1975 (supervisor: P. W. Sanford)

The development of a binary mask rocket experiment for the location of X-ray sources to an accuracy of 7' is described. The computer simulations which were used to design the fresnel zone plate for this for this experiment are presented. A considerable number of laboratory measurements were made to select the photographic emulsion for the detector and these are discussed. A description is given of the payload used on SL602, and it is shown how mechanical imperfections affected its performance. The method used for the optical alignment of the experiment in the laboratory is described. Finally the details of the launch of the payload are presented.

The experimental and mathematical techniques which were developed for the analysis of the shadowgram are discussed. This analysis used a novel method of grain counting, and a scanning system using on-line computer control was developed for these measurements. Several laboratory studies were made using this method for the reconstruction of the photographic images, and the successful results which were obtained are described.

The latter half of the thesis is devoted to a discussion of the control and data handling software, which was developed for the Copernicus satellite, the calibration in orbit of the Mullard Space Science Laboratory experiment and some of the source locations that were obtained. A detailed description is given of the spacecraft and the relevant instrument functions. The two control computing systems, which were developed are described, and it is shown how one of these systems was coordinated with the data output to produce a reduced data format. The reflecting mirror telescopes were aligned by scans made across Sco X-1 and these measurements were confirmed by observations of other sources. The results of these measurements are presented, and it is shown how the instrument was used to locate GX 2+5 and 2U 0613+09.