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Closed Loop Performance. Laird Close and MagAO team SAC review. Requirement 1: The MagAO system high level VisAO Science Goal (bright stars). To obtain Strelhs of 10% or better in median seeing (0.7) on-axis at 0.8 um. This is equivalent to 190 nm rms residual wavefront error. Results.
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Closed Loop Performance Laird Close and MagAO team SAC review
Requirement 1: The MagAO system high level VisAO Science Goal (bright stars) • To obtain Strelhs of 10% or better in median seeing (0.7) on-axis at 0.8 um. • This is equivalent to 190 nm rms residual wavefront error.
Results Achieved “on-sky” 122 nm rms wavefront error at 800 Hz --- much better than 190nm goal
Closing the Loop at 1000 Hz At 1000 Hz closed loop we can achieve 65 nm rms error in tower ~95nm “on-sky”. NOTE that this is a linear stretch. This is much better than the 190 nm rms requirement.
See the movie! • http://www.youtube.com/watch?v=arjTorNtnCc&context=C4a1ba7aADvjVQa1PpcFNung4fzsYWr1SBl5fXtvLidUbAL4M9VSc= • Also see a video of how we close the loop here: • http://www.youtube.com/watch?v=wSiFoG8qgKI&context=C4a1917aADvjVQa1PpcFNung4fzsYWrw_ocFrcNJysPjatEvtUZbY=
Comparing to Simulations 68% “on-sky”
Clio2 • Clio2 can do excellent science with higher wavefront errors. Hence there is a need for Faint Star Performance as well to increase sky-coverage.
Goal 2: The MagAO system high level Clio2 Science Goal (faint stars) • To obtain Strelhs of 85% or better in median seeing (0.7”) on-axis at 3.8 um (L’) for a R=13 guide star. (or SR>96% at 8um on MIRAC4). • This is equivalent to 250 nm rms residual wavefront error.
Performance on Faint stars Here we have in z’ a Strehl of 13% or 210 nm rms error. This would be about 9.5% “on-sky” or 221 nm rms. This is better than the faint star goal of 250 nm rms
Summary: • Science requirement of <190 nm error for bright guide stars in median seeing is met, and improved on, by a significant margin with <95-122 nm rms achieved (800-1000 Hz, 400 modes) (by almost 2x lower in rms wavefront error). • Science requirement of <250 nm rms error for faint (R=13) guide stars is met and improved on with typically ~221 nm rms (200 Hz, 150 modes) is achieved.