MINIMUM ERROR IMAGE-RECONSTRUCTION FOR CODED MASK TELESCOPES

A new method is proposed for reconstructing the data from coded apertu re X/gamma-ray telescopes. This technique, based on the Wiener criteri on, is essentially a generalisation of existing Wiener filtering metho ds but is not confined to systems with position independent point sour ce response functions. The reconstruction method trades off the image degrading effects of statistical detector noise with the effects of im perfect source field coding, to produce a minimum error source field e stimate. It offers advantages if the coding properties of the mask-det ector configuration considered are not 'ideal' and is particularly use ful where multiple dithered observations are made of a given source fi eld. The proposed method is applied to simulated data and to data from a recent balloon flight of an experimental coded mask telescope. It i s shown to give better quality images than those formed by more conven tional methods.