Lucky imaging and adaptive optics on 10-m class telescopes: a real promise for diffraction limited imaging in the visible?

摘要

Traditionally thought as alternatives of each other, it has not been until very recently when Adaptive Optics (AO) and lucky imaging (LI) have been put to work together to achieve angular resolutions in the visible wavelengths comparable to those acquired with an ideal telescope. In this work the mutual benefits of combining fast frame selection (a.k.a. Lucky Imaging, LI) with Adaptive Optics (AO) on a 10-m class telescope are investigated by means of detailed Monte-Carlo numerical simulations. We investigate the expected image quality by looking at the Strehl Ratio (SR) at the optical R and I bands (around 650 and 800nm, respectively) and the potential of the technique to conduct high-contrast imaging. From our numerical simulations we are able to assess whether there is a net gain in the high-contrast capabilities when applying wavelet-based filtering techniques. As a test bench for what we should expect by moving on a 10-m class telescope we present recent results achieved with AO+LI at the 4-m William Herschel Telescope (WHT) by looking at the brown dwarf binary GJ569Bab.