The Gemini MCAO A Challenge and an Opportunity

The Gemini Multi-Conjugate Adaptive Optics system (MCAO) is an instrument under construction for Cerro Pachon that will deliver diffraction-limited images, with uniform image quality over a one arc minute field of view. It will do so by using several deformable mirrors optically conjugated at different altitudes, and five wavefront sensors using laser beacons as their guide sources, to measure and compensate for turbulence-induced phase aberrations in three dimensions. This new technique not only increases the compensated field of view by an order of magnitude or more and provides a uniform point spread function over this field, but also solves for the "cone effect", a consequence of the use of lasers as guide stars which in classical AO laser systems reduces the performance at short wavelengths on large telescopes.

In addition to the tenfold gain in angular resolution, MCAO also pushes the detection limit by 1.7 magnitudes on unresolved objects with respect to seeing limited images. This instrument on Gemini will provide a unique way to explore JWST-class science as soon as its commissioning in 2007.

The goal of these pages is to provide a concise view of MCAO:

• The case for MCAO science, formed at the 2000 Gemini/CfAO workshop
• Introduction to MCAO
• The MCAO module
• Instrumentation for MCAO
• Expected Performance: FWHM, Strehl ratio, Sky coverage...
  
• MCAO Document Archive
  

Last update July 14, 2006; Rachel Mason