MCAO testbed for European Solar Telescope (EST): first laboratory results for SCAO and GLAO configurations

  1. Noelia Feijóo 1
  2. Nicolás Rodríguez 1
  3. Luzma Montoya 1
  4. Jose Manuel González-Cava 2
  5. Yolanda Martin Hernando 1
  6. Haresh Chulani 1
  7. Miguel Nunez Cagigal 1
  8. Francisco González 1
  9. Jorge Quintero Nehrkorn 1
  10. Ángela Hernández-Delgado 1
  1. 1 Instituto de Astrofísica de Canarias
    info

    Instituto de Astrofísica de Canarias

    Santa Cruz de Tenerife, España

    ROR https://ror.org/03cmntr54

  2. 2 Universidad de La Laguna [Tenerife - SP]
Actas:
Adaptive Optics for Extremely Large Telescopes 7th Edition, ONERA

Año de publicación: 2023

Tipo: Aportación congreso

DOI: 10.13009/AO4ELT7-2023-098 GOOGLE SCHOLAR lock_openAcceso abierto editor

Resumen

A Multi-Conjugate Adaptive Optics (MCAO) testbed has been developed at the Instituto de Astrofísica de Canarias (IAC)as a prototype of the Adaptive Optics (AO) system for the European Solar Telescope (EST). EST is a 4.2-m telescope thatwill provide high resolution in a 60 arcsec circular Field of View (FoV). For this purpose, EST will be equipped with anMCAO system that will be integrated into the telescope’s optical path. The aim of the testbed is to analyse different sensingand wavefront correction strategies in order to check their suitability for EST. The testbed is a downscaled version of thetelescope that has been designed to replicate its main features, including the telescope aperture, the FoV and theatmospheric conditions representatives of the telescope site. It allows to set up of Single Conjugate Adaptive Optics(SCAO), Ground Layer Adaptive Optics (GLAO) and MCAO configurations, both for point-like and extended sources.For this purpose, three Shack-Hartmann Wavefront Sensors (SH-WFSs) have been developed and installed in the testbed.A High-Order Wavefront Sensor (HO-WFS) with 33x33 subapertures senses the on-axis 10 arcsec FoV. Additionally, aMulti-Directional WFS (MD-WFS) estimates the turbulence over the entire atmospheric volume. This WFS provides twopossible configurations: one high-order spatial resolution (HO-MD-WFS) and another low-order spatial resolution (LOMD-WFS). A pupil-conjugated deformable mirror (DM) with 820 actuators is currently available for SCAO and GLAOconfigurations. The introduction of two DMs conjugated to different altitudes will allow the correction of the wide field.The main aim of this contribution is to present the current state of the testbed and the first tests using a Multi-DirectionalWFS to perform the wavefront reconstruction. The test results show a possible approach to analyse the behaviour of thecontrol loop of an adaptive optics system. It is discussed whether control quality metrics can be used as an alternative toclassical optical quality metrics that are especially hard to standardize for solar observation. These metrics are relevantdue to the amount of data for GLAO.

Referencias bibliográficas

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