EAGLE multi-object AO concept study for the E-ELT

TL;DR

The paper presents a phase A study of the EAGLE multi-object adaptive optics system for the E-ELT, demonstrating its performance and sky coverage capabilities using laser and natural guide stars.

Contribution

It introduces a novel multi-object adaptive optics concept with detailed performance analysis for the E-ELT.

Findings

Achieves 35% Ensquared Energy in 75x75 mas^2 at H band

Uses 6 laser guide stars and up to 5 natural guide stars

Sky coverage near 90% at galactic latitude |b|~60

Abstract

EAGLE is the multi-object, spatially-resolved, near-IR spectrograph instrument concept for the E-ELT, relying on a distributed Adaptive Optics, so-called Multi Object Adaptive Optics. This paper presents the results of a phase A study. Using 84x84 actuator deformable mirrors, the performed analysis demonstrates that 6 laser guide stars and up to 5 natural guide stars of magnitude R<17, picked-up in a 7.3' diameter patrol field of view, allow us to obtain an overall performance in terms of Ensquared Energy of 35% in a 75x75 mas^2 spaxel at H band, whatever the target direction in the centred 5' science field for median seeing conditions. The computed sky coverage at galactic latitudes |b|~60 is close to 90%.