A study of MOAO behind GLAO for EAGLE

摘要

An MOAO corrected multi-IFU instrument, such as the EAGLE instrument proposed for the E-ELT has adeformable mirror correcting each IFU sub-field. Additionally, EAGLE will also use the E-ELT deformable M4mirror to apply a global (closed-loop) MOAO correction. Here, we investigate the impact on MOAO performanceif a global GLAO correction is applied across the whole field, rather than the optimised global MOAO correction(which may or may not be identical). The differences in M4 correction (between GLAO and optimal MOAO)will depend on the position of IFU pick-offs in the science field, and also on the turbulence, for example, MOAODM stroke may be minimised if more than the ground layer is corrected by the M4 DM, depending on howfast turbulence decorrelates across the field of view. We consider the impact on MOAO DM stroke, the effecton performance, and study both tomographic and non-tomographic GLAO corrections. Such a situation mayarise if for example a combined multi-object spectrograph and multi-IFU instrument is designed, such as wouldresult from the integration of EAGLE with another proposed E-ELT instrument. We demonstrate here thatperformance of EAGLE will not be significantly affected by being placed behind another such instrument. Theresults presented will be obtained using full end-to-endMonte-Carlo simulations using the Durham AO SimulationPlatform. We also present a number of algorithms which can be used to improve AO performance, both in pixelprocessing and multi-mirror control.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.