Ground-based coronagraphy with high-order adaptive optics

Russell B. Makidon, Anand Sivaramakrishnan, Christopher D. Koresko, Thomas Berkefeld, Marc J. Kuchner, Robert S. Winsor, Peter L. Wizinowich
2000 Adaptive Optical Systems Technology  
We simulate the actions of a coronagraph matched to diffraction-limited adaptive optics (AO) systems on the Calypso 1.2m, Palomar Hale 5m and Gemini 8.1m telescopes, and identify useful parameter ranges for AO coronagraphy on these systems. We model the action of adaptive wavefront correction with a tapered, high-pass filter in spatial frequency rather than a hard low frequency cutoff, and estimate the minimum number of AO channels required to produce sufficient image quality for coronagraphic
more » ... uppression within a few diffraction widths of a central bright object (as is relevant to e.g., brown dwarf searches near late-type dwarf stars). We explore the effect of varying the occulting image-plane stop size and shape, and examine the trade-off between throughput and suppression of the image halo and Airy rings. We discuss our simulations in the context of results from the 241-channel Palomar Hale AO coronagraph system, and suggest approaches for future AO coronagraphic instruments on large telescopes.
doi:10.1117/12.390396 fatcat:oje2rgjxavdmxhtzzf74dw3ama