We present an overview of the VISIR upgrade project. VISIR is the mid-infrared imager and spectrograph at ESO’s
VLT. The project team is comprised of ESO staff and members of the original VISIR consortium: CEA Saclay and
ASTRON. The project plan is based on input from the ESO user community with the goal of enhancing the scientific
performance and efficiency of VISIR by a combination of measures: installation of improved hardware, optimization of
instrument operations and software support. The cornerstone of the upgrade is the 1k by 1k Si:As Aquarius detector
array (Raytheon) which has demonstrated very good performance (sensitivity, stability) in the laboratory IR detector test
facility (modified TIMMI 2 instrument). A prism spectroscopic mode will cover the N-band in a single observation. New
scientific capabilities for high resolution and high-contrast imaging will be offered by sub-aperture mask (SAM) and
phase-mask coronagraphic (4QPM/AGPM) modes. In order to make optimal use of favourable atmospheric conditions a
water vapour monitor has been deployed on Paranal, allowing for real-time decisions and the introduction of a userdefined
constraint on water vapour. Improved pipelines based on the ESO Reflex concept will provide better support to
astronomers. The upgraded VISIR will be a powerful instrument providing background limited performance for
diffraction-limited observations at an 8-m telescope. It will offer synergy with facilities such as ALMA, JWST, VLTI
and SOFIA, while a wealth of targets is available from survey work (e.g. VISTA, WISE). In addition it will bring
confirmation of the technical readiness and scientific value of several aspects of potential mid-IR instrumentation at
Extremely Large Telescopes. The intervention on VISIR and installation of hardware has been completed in July and
commissioning will take place during July and August. VISIR is scheduled to be available to the users starting Oct 2012.
The European Southern Observatory (ESO) is preparing to upgrade VISIR, the mid-IR imager and spectrograph at the
VLT. The project team is comprised of ESO staff and members of the original consortium that built VISIR: CEA Saclay
and ASTRON. The goal is to enhance the scientific performance of VISIR and to facilitate its use by the ESO
community. In order to capture the needs of the user community, we collected input from the users by means of a webbased
questionnaire. In line with the results of the internal study and the input from the user community, the upgrade
plan calls for a combination measures: installation of improved hardware, optimization of instrument operations and
software support. The limitations of the current detector (sensitivity, cosmetics, artifacts) have been known for some
time and a new 1k x 1k Si:As Aquarius array (Raytheon) will be the cornerstone of the VISIR upgrade project. A
modified spectroscopic mode will allow covering the N-band in a single observation. Several new scientific modes (e.g.,
polarimetry, coronagraphy) will be implemented on a best effort basis. In addition, the VISIR operational scheme will be
enhanced to ensure that optimal use of the observing conditions will be made. Specifically, we plan to provide a means
to monitor precipitable water vapour (PWV) and enable the user to specify it as a constraint set for service mode
observations. In some regions of the mid-IR domain, the amount of PWV has a fundamental effect on the quality of a
given night for mid-IR astronomy. The plan also calls for full support by ESO pipelines that will deliver science-ready
data products. Hence the resulting files will provide physical units and error information and all instrumental signatures
will have been removed. An upgraded VISIR will be a powerful instrument providing diffraction-limited performance at
an 8-m telescope. Its improved performance and efficiency as well as new science capabilities will serve the needs of the
ESO community but will also offer synergy with various other facilities such as ALMA, JWST, VLTI and SOFIA. A
wealth of targets for detailed study will be available from survey work done by VISTA and WISE. Finally, the upgraded
VISIR will also serve as a pathfinder for potential mid-IR instrumentation at the European Extremely Large Telescope
(E-ELT) in terms of technology as well as operations.
CanariCam is the facility multi-mode mid-IR camera developed by the University of Florida for the 10-meter Gran
Telescopio Canarias (GTC) on La Palma. CanariCam has four science modes that provide the GTC community with an
especially powerful research tool for imaging, grating spectroscopy, coronagraphy, and dual-beam polarimetry.
Instrument commissioning in the laboratory at the University of Florida indicates that all modes perform as required, and
the next step is on-telescope commissioning. After commenting on the instrument status, we will review key features of
each of these science modes, with emphasis on illustrating each mode with science examples that put the system
performance, particularly the anticipated sensitivity, into perspective.
CanariCam is the facility multi-mode mid-IR camera developed by the University of Florida (UF) for the 10.4-
meter Gran Telescopio Canarias (GTC). CanariCam contains a 320 × 240-pixel Raytheon array, which will
Nyquist-sample the diffraction-limited point-spread-function at wavelengths longer than 8 microns, yielding a
field of view of 26"×19". In Aug. 2007, the University of Florida instrument team held a successful Acceptance
Testing (AT) of CanariCam. We describe key performance requirements, and compare these to the actual performance
during formal AT. Among the results considered are detector noise characteristics, image quality, and
throughput. We focus particularly on the unique dual-beam polarimetric modes. We have demonstrated that
with a half-wave plate, it achieves or exceeds the design goals for imaging both polarization planes simultaneously.
The Stratospheric Observatory for Infrared Astronomy (SOFIA) will provide new opportunities for high spectral resolution observations in the mid-infrared. To take advantage of these opportunities, we are developing EXES, the Echelon-Cross-Echelle Spectrograph. EXES will operate from 4.5 microns to 28.5 microns and achieve a velocity resolution of 3 km/s for λ < 10 μm. EXES will be a versatile instrument with three spectroscopic modes: cross-dispersed with R~105; long-slit with R~104; and long-slit with R~3000. The unique aspect of EXES is the high-resolution capability provided by a 1 meter echelon grating and a 256 by 256 low-background Si:As IBC detector. Much of the design and operation of EXES has already been validated by the performance of a very similar ground-based instrument, the Texas Echelon-Cross-Echelle Spectrograph (TEXES). We present here a summary of the EXES design and current status; a brief description of ground-based, high spectral resolution, mid-infrared results; and a look ahead to the possible science using SOFIA and EXES.
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