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Table 1.
Main parameters of the post-AO PSF modeling.
| Turbulent atmosphere parameters | |
| Fried parameter r 0 (at 500 nm) | 7 cm and 5 cm |
| ⇒ Resulting seeing angle (at 500 nm) | 1.44″ and 2.02″ |
| Number of turbulent layers | 3 |
| Layer altitudes | [0, 7852, 13252] m |
| Layer velocities | [10, 10, 10] m−1s |
Layer  profile relative weight |
[0.942, 0.038, 0.02] |
| Wavefront outer scale ℒ0 | 27 m |
| Telescope parameters | |
| Effective diameter | 4 m |
| Obstruction ratio | none (off-axis mirror) |
| AO system parameters | |
| Deformable mirror configuration | 44 × 44 |
| Shack–Hartmann configuration | 43 × 43 |
| Wavefront sensing exposure time [ms] | 2 |
| Additional AO-loop delay time [ms] | 0.5 |
| Wavefront sensing RON [e− rms] | 20 |
| Additional anisoplanatic off-axis angle | 2.6″ |
| Closed-loop gain | 0.5 |
| ⇒ Resulting Strehl ratio (at 630 nm) | 0.30 and 0.12 |
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