Getting the most out of C.O.A.S.T

PREFACE The work described in this thesis was carried out under the supervision of Dr P. The work is my own except where otherwise stated and was not done in collaboration with others. It is the not the same as any other dissertation submitted for a degree, diploma or any other qualification at any university. This thesis does not exceed 60 000 words. ORIGINALITY Chapter 1 is a review of developments in optical aperture synthesis and is not original work. Chapter 2 considers the techniques estimating of fringe visibilities from photon-noise-limited data and is mostly a review of previous work, although some of the analysis is my own. Chapters 3–6 are original except where otherwise stated. The delay line described in chapter 7 is based on the design developed by Connes [16], but the specific implementation is my own. Chapter 8 describes experiments which are a continuation of the work of Baldwin et al. [6] and Haniff et al. [37], but the specific work descibed here is my own. Chapter 9 is original except where otherwise stated. ACKNOWLEDGEMENTS I would like to thank everyone in the radioastronomy group who helped to provide a congenial atmosphere in which to work. In particular I would like to thank my useful discussions, for their constructive comments on the manuscript and for their respective senses of humour. I am also indebted to Chris Haniff for lessons in practical interferometry with a hammer and chisel, to Graham Woan for interesting discussions on ideas which may or may not have been obvious, and to Alan Matthews for continually reminding me that there was life beyond radioastronomy. I would like to thank the staff at the Roque de Los Muchachos Observatory in La Palma for their assistance during my observing run there, and Jan Noordam for providing the 'photon-tagging' software for the IPCS. 3 Optimising the aperture size and the integration time 35 3.