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NAOMI is the AO system of the William Herschel Telescope on La Palma. It delivers near-diffraction-limited imaging in the IR, and a significantly improved PSF at optical wavelengths. The science instrumentation includes an IR imager (INGRID), an optical integral-field spectrograph (OASIS) and a coronograph which may be placed in the light path to either instrument. 19 science programmes were...
This paper will review all Adaptive Optics systems already in operation or in construction at ESO. Roadmap toward the future AO systems both for the VLT and for OWL will be discussed.
Altair is the facility adaptive optics (AO) system of the Gemini North Telescope. It was designed and built at the National Research Council of Canada’s Herzberg Institute of Astrophysics. It was delivered to Gemini in October 2002 and recorded its first corrected image on November 20th 2002. Since then, Altair underwent a total of 7 weeks of commissioning, including two weeks completely...
In this paper, we report on observations of faint companions and circumstellar disks at the Palomar 200-inch telescope. As a result, we present successful detection of the low-mass companion to HR 7672 and of the dusty disk around HD 141569 using ground-based coronagraphy. Finally, we will present the first promising images obtained with a Four-Quadrant Phase-Mask coronagraph on NACO at the...
Adaptive Optics Systems for Extremely Large Telescopes (ELT) will need new wavefront sensing concepts to deploy their full capabilities. In this paper we exemplify the necessity of new wavefront sensing ideas by discussing briefly some major problems and present as a possible solution the pseudo infinite guide star sensor (PIGS). A prototype of a PIGS sensor was already built in the laboratory,...
In this article, we present the envisioned adaptive optics (AO) system for MUSE (Multi-Unit Spectroscopic Explorer), a visible light integral field spectrograph for the VLT. Two modes, a low spatial resolution and a high spatial resolution (diffraction limited) have been studied. The first mode will cover a 1’ field of view (FOV) with improved seeing and the second mode a 10” FOV with diffraction...
A short summary of the existing and planned observational capabilities of NAOS-CONICA (NACO) is given, including all possible setups, those which are currently offered to the user community as well as other setups existing since first commissioning but not officially available (yet). There are three additional modes in preparation or consideration: The Simultaneous Differential Imager (SDI)...
Young (100 Myr old) extra-solar planets are 100000 times more self-luminous than old (5 Gyr) extra-solar planets, whereas their primary stars are only slightly (2–5 times) brighter when this young. Currently the majority of such young stars that are nearby (≤ 50pc) are located in the southern star forming regions and associations ( δ ≤ –20 deg.). To detect a faint point source (a planet)...
The first ESO adaptive optics system instrument, NACO, installed at the VLT has been offered to the astronomical community and used on a regular basis in service and visitor mode for just over one year. We present an overview of the first year of operations and an analysis of some NACO technical and calibration data.
The performance of adaptive optics (AO) systems is more often discussed in the context of imaging capability. However, it is also a powerful front-end optics for a spectrograph to gain physical and chemical informations in diminutive objects. We have dedicated ourselves to spectroscopy with AO at Subaru, aiming unique science relatively not explored to date. In the course of the process,...
The verification of data and the monitoring of instrument performance – known collectively as quality control (QC) – are an integral part of the paradigm of VLT operations. This is especially true for complex instruments, such as NAOS-CONICA, which is the first adaptive optics instrument at the ESO VLT. In this paper, we discuss several of the tools we use to check and monitor instrument...
We present a preliminary study of photometric and astrometric measurements from adaptive optics (AO) observations of the Galactic Bulge. We compare two different observations of the same crowded stellar region in H-band, one detected with the NICMOS camera on HST and one using NACO, the AO system on the VLT at ESO. The AO image field is affected by anisoplanatism, with the natural guide star...
In this work an analytical description of the NACO PSF with a minimum number of parameters is sought. These parameters are governed by the observational characteristics and the location of the PSF with respect to the guide star. The first order approximation of the PSF can then be used for image deconvolution. The analysis and modelling of the PSF was performed using images of a given position...
During the instrument commissioning phase end of 2001, the object Tauri was observed with the NAOS-CONICA system at ESO VLT unit YEPUN. For experimental purposes as also for demonstrating the capabilities of the adaptive optics control, two short-exposure image sequences were recorded – one with activated compensation of the disturbing atmosphere (so-called “closed loop” mode: sample...
The scientific impact of adaptive optics observations carried out so far has been limited by the combined effects of the variability of the guide star PSF as well as the anisoplanacy unavoidably accompanying single-layer pupil-conjugated adaptive optics observations. In this paper we present results from a combined adaptive optics/ SCIDAR run at the Calar Alto observatory with the adaptive...
The SINFONI (SINgle Far Object Near-ir Investigation) instrument is developed jointly by ESO, MPE and NOVA, and combines integral field spectroscopy with adaptive optics in one instrument [1,2]. The instrument will be available at ESO’s VLT in 2004. The AO module of the instrument is based on a 60-element curvature wavefront sensor (CWS) combined with a bimorph deformable mirror. It will...
In order to evaluate the performances of Adaptive Optics (AO), pertinent evaluation of the error budget must be provided. This can be performed with end-to- end simulations or within analytical development. Here an innovative analytical method, first introduced by Rigaut et al.[2] and developed by Jolissaint et al.[1], is generalized and applied to the computation of AO corrected phase screens...
An overview of calibrations required to reach ultimate performances of AO systems is presented. Both AO loop and non-common path aberration calibrations are considered. Impact of mis-calibrations are studied. NAOS-CONICA examples are proposed to illustrate each calibration procedure.
The turbulence structure of the atmosphere is the primary limitation to adaptive optics system performance on extremely large telescopes — driving current world-wide site testing campaigns. The potential for adaptive optics correction on extremely large telescopes located at Dome C station on the Antarctic plateau is investigated here. Due to the unique atmospheric characteristics of this...
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