AO Instruments

Contents


Systems in operation at the VLT

NACO

NaCo sets out for NAOS-CONICA. It is installed at the Nasmyth B focus of UT4. It provides adaptive optics assisted imaging, imaging polarimetry, coronography and spectroscopy, in the 1-5 microns range. More information is available on a separate page.

CRIRES

The VLT cryogenic high-resolution infrared echelle spectrograph CRIRES is located at the Nasmyth focus A of UT1 (Antu). It provides a resolving power of up to 105 in the spectral range from 1 to 5 µm when used with a 0."2 arcsec slit. CRIRES can boost all scientific applications aiming at fainter objects, higher spatial (extended sources), spectral and temporal resolution. Simultaneous spectral coverage is maximized through a mosaic of four Aladdin III InSb arrays providing an effective 4096 x 512 focal plane detector array in the focal plane. Adaptive Optics (MACAO - Multi-Applications Curvature Adaptive optics) is used to optimize the signal-to-noise ratio and the spatial resolution. More information is available on a separate page.

SINFONI

SINFONI is a near-infrared (1.1 - 2.45 µm) integral field spectrograph fed by an adaptive optics module, currently installed at the Cassegrain focus of UT4. The spectrograph operates with 4 gratings (J, H, K, H+K) providing a spectral resolution around 2000, 3000, 4000 in J, H, K, respectively, and 1500 in H+K - each wavelength band fitting fully on the 2048 pixels of the Hawaii 2RG (2kx2k) detector in the dispersion direction. The spatial resolution is selectable from 0.25", 0.1" to 0.025" per image slice, which corresponds to a field-of-view of 8"x8", 3"x3", or 0.8"x0.8" respectively. The instrument can be also used for seeing limited open loop observations. More information is available on a separate page.

MACAO

MACAO, which stands for Multi-Application Curvature Adaptive Optics, is an ESO in-house developed 60 elements curvature adaptive optics system. MACAO-VLTI is the application of this AO principle to be used by the VLT interferometer (VLTI). Four MACAO-VLTI systems have been installed at the each UT Coude' focii feeding the VLTI delay lines with a corrected IR beam from 1000-13000nm with up to 50% Strehl @ 2.2microns.

Systems in development for the VLT

SPHERE

The prime objective of the Spectro-Polarimetric High-contrast Exoplanet Research (SPHERE) instrument for the VLT is the discovery and study of new extra-solar giant planets orbiting nearby stars by direct imaging of their circumstellar environment. SPHERE will be located at the Nasmyth focus of the VLT. The instrument as shown in the figure above is composed of 4 major subsystem: the common path including the powerfull AO system and the three science instruments IRDIS, IFS and ZIMPOL each fed by a sophisticated pupil apodized Lyot, Lyot, or phase mask coronagraph. More information is available on a separate page.

AOF

The Adaptive Optics Facility (AOF) aim is to upgrade a single 8m Unit telescope of the Paranal Observatory with an Adaptive Secondary Mirror. The goal is to make this telescope an Adaptive Telescope providing turbulence corrected images at all focii, without the addition of adaptive modules and supplementary optics in front of the instruments. The concept is far more reaching than only a deformable secondary mirror (DSM) since the instrument park is optimized to benefit from this upgrade. Several novel adaptive correction modes are also envisioned making use of a sophisticated Laser launch facility that will provide 4 Laser artificial guide stars for wavefront sensing. The AOF booklet gives an overview of the AOF.

Sub-systems of the AOF

In addition to the DSM, the AOF has two AO modules:

and 4 Laser guide stars. The AOF will be tested on the ASSIST test bench before going on the VLT.

Demonstrators of new Adaptive Optics instruments

MAD

The Multi-Conjugate Adaptive Optics Demonstrator (MAD) is a prototype MCAO system which aims to demonstrate in the laboratory and on sky the feasibility of different MCAO reconstruction techniques in the framework of the E-ELT concept and the 2nd Generation VLT Instruments. After an extended period of laboratory testing MAD was installed at the VLT Nasmyth focus for performing some validation runs and science demosntration runs. The system was finally dismounted and sent back to ESO-Garching for further tests in laboratory.

The MAD project is led and developed by ESO with the collaboration of INAF-OsservatorioAstrofisico di Arcetri (INAF-OAA), the INAF-Osservatorio Astronomicodi Padova (INAF-OAPD) and the Faculdade de Ciências de Universidade de Lisboa (FCUL).

More information is available on a separate page.

HOT

The high Order Test Bench was developped in the frame of the European Programmme FP6 Opticon JRA1 to implement extreme adaptive optics on a test bench with realistic telescope conditions reproduced by star and turbulence generator. The objective was to compare two different wavefront sensors including their behavior to different errors during calibration and other noises. The complete list of objective as well as the test are presented on a separate page.

Systems studies for the E-ELT

The Adaptive Telescope

In the frame of the E-ELT project the Adaptive Optics department is following the detailed design phase of two sub units of the telescopes:

The calibration unit feasibility study is also followed by the Adaptive optics Department.

AO instruments phase A studies

Two adaptive optics modules (ATLAS, MAORY) and two AO assisted instruments (EAGLE and EPICS) are currently studied by external consortia. More information is available on a separate page.