You are hereBlogs / admin's blog / Excellent results from recent LGS run...

Excellent results from recent LGS run...


By admin - Posted on 30 October 2008

The most recent run for the LGS team (10/13 – 10/17) proved incredibly successful, producing some very exciting results. Following is the key results and images supplied by Michael Lloyd-Hart and the LGS team.

 

The ground-layer AO compensation resulted in dramatic improvements in image quality over the full 2′ x 2′ field of view of the Pisces camera in the J, H and K NIR wavebands. Native seeing in K of 0.85″ was corrected to 0.25″ with the AO. The first image below shows a great example of the native seeing of 0.61″ being corrected to 0.22″ with closed loop for a 10″ FOV at the centre of M36. The second image demonstrates the quality of the correction over the entire 2′ FOV of the camera – for native seeing of 0.86″ corrected to 0.27″.  The table below quantitatively shows the uniformity of the correction over the FOV. The plot shows achieved FWHM (“) versus distance (“) from the tip/tilt natural guide star – again demonstrating how good the correction is regardless of object position in the field.

Ks 60 second exposure: Showing a Ks, 60 second exposure of a 10″ region at the centre of M36. Native 0.66″ seeing GLAO corrected to 0.22″.Ks 60 second exposure: Showing a Ks, 60 second exposure of a 10″ region at the centre of M36. Native 0.66″ seeing GLAO corrected to 0.22″.  Full Pisces FOV: Showing image quality over the full Pisces FOV, open loop 0.86″ seeing corrected to 0.27″Full Pisces FOV: Showing image quality over the full Pisces FOV, open loop 0.86″ seeing corrected to 0.27″Correction Quality Plot: Shows quality of the correction over the full field. FWHM with respect to distance from the tip/tilt natural guide star.Correction Quality Plot: Shows quality of the correction over the full field. FWHM with respect to distance from the tip/tilt natural guide star.

 

The system is now very robust, staying closed unattended for tens of minutes at a time. The attained closed loop results are consistent with the open loop predictions for H & K and even better in J. It will be exciting to know what results are achieved in Z or I. Thanks again to Michael Lloyd-Hart for these wonderful images and congratulations to the whole team on the excellent results.