In this paper, we summarize the analysis made on various Adaptive
Optics (AO) modes (including Shack-Hartmann (SH) and Pyramid Wavefront Sensors (PWS)) for the OverWhelmingly Large telescope (OWL). We will show some early results of the performance to be expected with a first generation AO system, working in the infrared.
Several telescope diameters were considered to see the variations as a
function of telescope diameter. This is also compatible with the
concept of "grow a telescope" where the telescope diameter of OWL
grows from 60m to 100m as a function of time.
In a first phase, to simplify the problem, the effects of the central
obstruction were neglected. However, for the Shack-Hartmann (SH)
simulations, additional simulations were carried out with a simulated
OWL pupil, including segmentation errors.
We show some early results for a ground-layer correction system, working with three natural guide stars (NGSs) and a single deformable mirror (DM). An MCAO system based on 2 DMs, 3 NGSs is also investigated. For the last two systems, our results are found to be in
very good agreement with Cibola, an analytical AO modeling tool. We show that some outer scale of turbulence effects improve slightly the
correction quality when going from a telescope diameter of 10m to