Abstract
The sensitivity of hexagonal geometry, gamma-ray coded aperture telescopes has been studied in order to investigate the trade-off between the nominal angular resolution and the mean reconstructed image signal to noise ratio (SNR) that occurs when a pixellated detector array is used and images are retrieved by a simple correlation analysis. Without high fine sampling of the coded mask by the detector plane, the image SNR is seriously compromised if the source under observation lies close to a sky pixel boundary. Increasing the integer sampling partially restores the image SNR, but at the expense of the angular resolution. A method of improving the image SNR across sky pixel boundaries has been investigated, resulting in sky images that are free from the SNR modulation encountered with integer fine sampling of the shadowgram, and without any significant loss in angular resolution.
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© 1995 Springer Science+Business Media Dordrecht
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Jupp, I.D., Green, A.R., Dean, A.J. (1995). Optimised Sampling for Hexagonal Array Coded Mask Telescopes. In: Bassani, L., Di Cocco, G. (eds) Imaging in High Energy Astronomy. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-0407-4_29
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DOI: https://doi.org/10.1007/978-94-011-0407-4_29
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-4182-9
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