Impact of Sodium Layer variations on the performance of the E-ELT MCAO module

TL;DR

This paper investigates how sodium layer variations affect the performance of the E-ELT's MCAO system using simulations based on real sodium layer data.

Contribution

It provides a detailed analysis of sodium layer variability impacts on MCAO performance through end-to-end simulations.

Findings

Sodium layer variability induces low/medium order perturbations.

These perturbations affect the overall MCAO system performance.

Simulation results highlight the importance of sodium layer stability for optimal AO performance.

Abstract

Multi-Conjugate Adaptive Optics systems based on sodium Laser Guide Stars may exploit Natural Guide Stars to solve intrinsic limitations of artificial beacons (tip-tilt indetermination and anisoplanatism) and to mitigate the impact of the sodium layer structure and variability. The sodium layer may also have transverse structures leading to differential effects among Laser Guide Stars. Starting from the analysis of the input perturbations related to the Sodium Layer variability, modeled directly on measured sodium layer profiles, we analyze, through a simplified end-to-end simulation code, the impact of the low/medium orders induced on global performance of the European Extremely Large Telescope Multi-Conjugate Adaptive Optics module MAORY.