Download Closed Loop Performance

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
Results
Achieved “on-sky” 122 nm rms wavefront error at 800 Hz --- much better than
190nm goal
Comparing to Simulations
ERROR
BUDGET
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=arjTorNt
nCc&context=C4a1ba7aADvjVQa1PpcFN
ung4fzsYWr1SBl5fXtvLidUbAL4M9VSc=
• Also see a video of how we close the loop
here:
• http://www.youtube.com/watch?v=wSiFoG
8qgKI&context=C4a1917aADvjVQa1PpcF
Nung4fzsYWrw_ocFrcNJysPjatEvtUZbY=
Comparing to Simulations
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 skycoverage.
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 <95122 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.