MICADO will enable the ELT to perform diffraction limited near-infrared observations at first light. The instruments capabilities focus on imaging (including astrometric and high contrast) as well as single object spectroscopy. This contribution looks at how requirements from the observing modes have driven the instrument design and functionality. Using examples from specific science cases, and making use of the data simulation tool, an outline is presented of what we can expect the instrument to achieve.
MICADO will equip the E-ELT with a first light capability for diffraction limited imaging at near-infrared wavelengths. The instruments observing modes focus on various flavours of imaging, including astrometric, high contrast, and time resolved. The
re is also a single object spectroscopic mode optimised for wavelength coverage at moderately high resolution. This contribution provides an overview of the key functionality of the instrument, outlining the scientific rationale for its observing modes. The interface between MICADO and the adaptive optics system MAORY that feeds it is summarised. The design of the instrument is discussed, focussing on the optics and mechanisms inside the cryostat, together with a brief overview of the other key sub-systems.
We report on our ongoing efforts to ensure that the MICADO NIR imager reaches differential absolute (often abbreviated: relative) astrometric performance limited by the SNR of typical observations. The exceptional 39m diameter collecting area in comb
ination with a powerful multi-conjugate adaptive optics system (called MAORY) brings the nominal centroiding error, which scales as FWHM/SNR, down to a few 10 uas. Here we show that an exceptional effort is needed to provide a system which delivers adequate and calibrateable astrometric performance over the full field of view (up to 53 arcsec diameter).
In this paper, we present the design and the expected performance of the classical Lyot coronagraph for the high contrast imaging modes of the wide-field imager MICADO. MICADO is a near-IR camera for the Extremely Large Telescope (ELT, previously E-E
LT), with wide-field, spectroscopic and coronagraphic capabilities. MICADO is one of the first-light instruments selected by the ESO. Optimized to work with a multi-conjugate adaptive optics corrections provided by the MOARY module, it will also come with a SCAO correction with a high-level, on-axis correction, making use of the M4 adaptive mirror of the telescope. After presenting the context of the high contrast imaging modes in MICADO, we describe the selection process for the focal plane masks and Lyot stop. We will also show results obtained in realistic conditions, taking into account AO residuals, atmospheric refraction, noise sources and simulating observations in angular differential imaging (ADI) mode. Based on SPHERE on-sky results, we will discuss the achievable gain in contrast and angular separation provided by MICADO over the current instruments on 10-m class telescopes, in particular for imaging young giant planets at very short separations around nearby stars as well as planets on wider orbits around more distant stars in young stellar associations.
As an in-house instrument developmental activity at ARIES, the 4Kx4K CCD Imager is designed and developed as a first-light instrument for the axial port of the 3.6m DOT. The f/9 beam of the telescope having a plate-scale of ~ 6.4 arc-sec/mm is utiliz
ed to conduct deeper photometry within the central 10 arc-min field of view. The pixel size of the blue-enhanced liquid Nitrogen cooled STA4150 4Kx4K CCD chip is 15 micron, with options to select gain and speed values to utilize the dynamic range. Using the Imager, it is planned to image the central ~ 6.5x6.5 arc-min^2 field of view of the telescope for various science goals by getting deeper images in several broad-band filters for point sources and objects with low surface brightness. The fully assembled Imager along with automated filter wheels having Bessel UBVRI and SDSS ugriz filters was tested in late 2015 at the axial port of the 3.6m DOT. This instrument was finally mounted at the axial port of the 3.6m DOT on 30th March 2016 when the telescope was technically activated jointly by the Prime Ministers of India and Belgium. This instrument is expected to serve as a general purpose multi-band deep imaging instrument for variety of science goals including studies of cosmic transients, active galaxies, star clusters and optical monitoring of X-ray sources discovered by the newly launched Indian space-mission called ASTROSAT and follow-up of radio bright objects discovered by the GMRT.
The Mid-infrared ELT Imager and Spectrograph (METIS) will provide the Extremely Large Telescope (ELT) with a unique window to the thermal- and mid-infrared (3 - 13 microns). Its single-conjugate adaptive optics (SCAO) system will enable high contrast
imaging and integral field unit (IFU) spectroscopy (R~100,000) at the diffraction limit of the ELT. This article describes the science drivers, conceptual design, observing modes, and expected performance of METIS.