With ARGOS, three lasers are used as Rayleigh beacons on each telescope to directly sense the mean ground layer turbulence across the LUCI 4′ field of view. It corrects more Zernike modes than the 10 done with ESM mode, and the system runs at 1 kHz so DIQ is better with ARGOS than with ESM. ARGOS still needs a guide star for the AGw to do the initial collimation of the telescope at new positions, but with a restricted patrol field because of the laser dichroic (as shown in the LUCI AGw unit Patrol Field Image below).
With ARGOS there is about a factor of 2 improvement over ACTIVE (seeing-limited) mode. This allows the user to use narrower slits (0.5″ vs 1.0″ slits), that give you higher resolution and lower backgrounds (higher SNR). The trade off is that ARGOS will always be block scheduled because of additional staff and resources to run the system. Use of the laser requires targets to have advanced clearance from Space Command. Also overheads are higher, and considerations about the air traffic must be considered when planning targets.
See Enhanced Seeing Mode (ESM) page for details about ESM operations and Diffraction Limited (AO) for details about full AO.
ARGOS is currently not available for on-sky science.