The Laser Guide Star Facility (LGSF) of Gran Telescopio Canarias (GTC) will be in charge of generating a Laser Guide Star (LGS) in the high atmosphere for the GTC Adaptive Optics System (GTCAO) to measure and correct the effect of the atmospheric turbulence. This proceeding analyses the thermal response of the LGS launch systems in operation under the direct action of the laser, and its interaction with respect GTC Telescope environment.
HARMONI is the first light, adaptive optics assisted, integral field spectrograph for the European Southern Observatory’s Extremely Large Telescope (ELT). A work-horse instrument, it provides the ELT’s diffraction limited spectroscopic capability across the near-infrared wavelength range. HARMONI will exploit the ELT’s unique combination of exquisite spatial resolution and enormous collecting area, enabling transformational science. The design of the instrument is being finalized, and the plans for assembly, integration and testing are being detailed. We present an overview of the instrument’s capabilities from a user perspective, and provide a summary of the instrument’s design. We also include recent changes to the project, both technical and programmatic, that have resulted from red-flag actions. Finally, we outline some of the simulated HARMONI observations currently being analyzed.
HARMONI is the first light visible and near-IR integral field spectrograph for the Extremely Large Telescope (ELT). This instrument covers a large spectral range from 450nm to 2450nm with resolving powers from 3500 to 18000 and spatial sampling from 60mas to 4mas. The Pre-Optics (sub-system under the responsibility of the IAC) contains five mechanisms working at cryogenic temperatures. Three types of mechanisms are needed to provide full functionality: wheels (2), turrets (2) and shutter (1). The wheels and turrets, supported by a series of radial and axial bearings, are driven by stepper motors through a system of gears that provide mechanical reduction. In addition, the focal plane mask wheel has a detent system to improve repeatability to within +/- 2.5 microns. Finally, the shutter consists in two masks with three clover shape blades mounted on a stepper motors. The work describes the main IPO mechanisms requirements and the design developed for every module. We also present some of the prototypes developed to proof the concepts adopted in the design..
HARMONI is the first light visible and near-IR integral field spectrograph for the Extremely Large Telescope (ELT). It covers a large spectral range from 450nm to 2450nm with resolving powers from 3500 to 18000 and spatial sampling from 60mas to 4mas. The IFS Pre-Optics (IPO), sub-system under the responsibility of the Institute of Astrophysics of the Canary Islands (IAC), contains 30 opto-mechanical mounts working at cryogenic temperatures and are classified into three types depending on the mirror shape: [1] - Sprung kinematic mount for flat mirrors: By spring loading, the mirror is constrained radially against a Vee-groove. - Thermally compensated kinematic sprung mount for power mirrors: It is similar to the previous mount but the radial pads compensate mirror radial movement. - Bonded mount for toroidal mirrors: The mirror is bonded to a rear invar pad, which serves as an interface to the support. This work describes the designs developed for the opto-mechanical modules of the Instrument IPO in order to comply with the sub-system requirements. We also present the prototypes developed to prove some of the adopted concepts in the design.
HARMONI is the adaptive optics assisted, near-infrared and visible light integral field spectrograph for the Extremely Large Telescope (ELT). A first light instrument, it provides the work-horse spectroscopic capability for the ELT. As the project approaches its Final Design Review milestone, the design of the instrument is being finalized, and the plans for assembly, integration and testing are being detailed. We present an overview of the instrument’s capabilities from a user perspective, provide a summary of the instrument’s design, including plans for operations and calibrations, and provide a brief glimpse of the predicted performance for a specific observing scenario. The paper also provides some details of the consortium composition and its evolution since the project commenced in 2015.
The Natural Guide Star Adaptive Optics system for the Gran Telescopio Canarias (GTC) is in its integration phase, and meanwhile the Laser Guide Star update, which will follow two years later, has recently passed its Preliminary Design Phase. This LGS Facility will feature a TOPTICA Na laser, and it will open up the scientific possibilities of GTC enlarging the sky coverage of the AO system and allowing to study at high resolution more scientific targets. A trade-off study was undertaken to decide, among other details, the launching position of the laser and the feasibility of a further upgrade to an MCAO system vs technical complexity, cost and maintenance. As part of this study we have analysed the performance of the GTCAO LGS system to ensure that it will fulfil the specifications in all the different scenarios. Complete end-to-end (E2E) simulations have been performed using the versatile Durham AO Simulation Platform (DASP), including not only real atmospheric profiles from Observatorio del Roque de los Muchachos but also the measured windshake spectrum of the secondary mirror of GTC, the different control loops (TT, DM, focus), the laser uplink jitter and launching telescope divergence, the segmented primary mirror and it's cophasing residual errors, the rotating pupil etc... In this contribution we present a detailed error budget of the system and the results of the E2E simulations that show the impact that such a system will have on the science done with GTC.
HARMONI is a visible and near-infrared (0.5 to 2.45 μm) integral field spectrograph, providing the E-ELT's core spectroscopic capability, over a range of resolving powers from R (λ/Δλ) ~ 3500 to ~18000. The instrument provides simultaneous spectra of ∼32000 spaxels arranged in a sqrt(2):1 aspect ratio contiguous field. The pre-optics take light entering the science cryostat (from the telescope or calibration system), reformatting and conditioning to be suitable for input for the rest of the instrument. This involves many functions, mainly relaying the light from the telescope focal plane to the integral field unit (IFU) focal plane via a set of interchangeable scale changing optics. The pre-optics also provides components including a focal plane mask wheel, cold pupil masks, spectral order sorting filters, a fast shutter, and a pupil imaging capability to check telescope/instrument pupil alignment. In this paper, we present the optical design of the HARMONI pre-optics at Preliminary Design Review and, in particular, we detail the differences with the previous design and the difficulties salved to the Preliminary Design Review.
HARMONI is a visible and near-infrared (0.47 to 2.45 μm) integral field spectrograph, providing the ELT's core spectroscopic capability at first light. A pre-optics subsystem provides four selectable spatial pixel scales, in addition to other beam conditioning functions such as shutter and pupil masks. For the validation of the mechanisms in charge of these functions (fast shutter and the plane mask wheel) we have planned some prototypes to test the design solutions.
The focal plane mask wheel sits in the input focus of the cryostat. It provides 16 user-selectable positions for masks (28x40 mm) used in observation. The key driver for this mechanism is the high repeatability (±2.5 μm) required, equivalent to ~1mas in the input focal plane. The IAC has previously designed, manufactured, tested and put in operation cryogenic wheels with high repeatability; however, the challenge of obtaining a wheel with such repeatability requires testing new concepts of detent positioning systems.
The shutter allows for exposures shorter than the minimum read time of the near-IR detectors and is needed for any CCD observations with the visible cameras. A dual shutter design is needed to achieve the necessary open/close times (<20 ms), but this also provides some redundancy and a graceful failure mode for this critical device. To mitigate risks on the proper behaviour of a fast cryogenics shutter a prototype based on a simple concept has been manufactured. We present the design and results for the performed cryogenic tests of a mask wheel and a shutter prototypes that we have developed.
This contribution is focused on the innovative aspects of the design of the Laser Guide Star (LGS) Facility for the Gran Telescopio Canarias (GTC) Adaptive Optics (GTCAO) System [6]. After a trade-off process considering different alternatives, a preliminary opto-mechanical design was defined, based on a “TOPTICA SodiumStar” laser to be launched on-axis. To maximize throughput, different novelties around the optical, and mechanical design of the Laser Launch System, including the Laser Head, the Beam Transfer Optics and the Launch Telescope are emphasized in this paper. In particular, all the elements of the Laser Launch System have been compacted to be placed at the backside envelope of the GTC M2 mechatronics. To fit in that envelope the thermal enclosure of the Laser Head had to be redefined to avoid mechanical interferences and science beam vignetting. An innovative closed-loop Laser Head cooling approach was defined to be also arranged at the backside of GTC M2. Performance simulations running in parallel to the on-axis LGS design could not determine any difference in performance between the on-axis and the off-axis launch. Hence, considering the higher packaging and maintenance complexity required by the on-axis launch, GTC decided to define the off-axis configuration as the new baseline approach. All the solutions already defined for the on-axis approach that were applicable to the new off-axis baseline were reused. To reduce the cost of future upgrades, the LGS design allows generating and launching several LGS with just one launch telescope splitting the light from the Laser Head. In parallel with keeping the volume of the facility to a minimum, an effort to keep its maintenance as simple as possible has been also made to avoid the impact on the telescope operational costs.
HARMONI is the E-ELT’s first light visible and near-infrared integral field spectrograph. It will provide four different spatial scales, ranging from coarse spaxels of 60 × 30 mas best suited for seeing limited observations, to 4 mas spaxels that Nyquist sample the diffraction limited point spread function of the E-ELT at near-infrared wavelengths. Each spaxel scale may be combined with eleven spectral settings, that provide a range of spectral resolving powers (R ~3500, 7500 and 20000) and instantaneous wavelength coverage spanning the 0.5 – 2.4 μm wavelength range of the instrument. In autumn 2015, the HARMONI project started the Preliminary Design Phase, following signature of the contract to design, build, test and commission the instrument, signed between the European Southern Observatory and the UK Science and Technology Facilities Council. Crucially, the contract also includes the preliminary design of the HARMONI Laser Tomographic Adaptive Optics system. The instrument’s technical specifications were finalized in the period leading up to contract signature. In this paper, we report on the first activity carried out during preliminary design, defining the baseline architecture for the system, and the trade-off studies leading up to the choice of baseline.
KEYWORDS: Cryogenics, Prototyping, Camera shutters, Computer programming, Sensors, Commercial off the shelf technology, Temperature metrology, Computer aided design, Control systems, Photonic integrated circuits
HARMONI is an integral field spectrograph working at visible and near-infrared wavelengths. The instrument will be part of the first-light complement at the E-ELT. The IAC is in charge of several work packages and the design of two important components is ongoing: A 'Cryogenic Pupil Mask Rotator' based on a direct drive brushless motor, and a 'Cryogenic Fast Shutter' based on voice coil. One of the main goals of these developments is the use of COTS (Commercial-Off-The-Shelf) parts since their use will reduce costs and short the schedule. Nevertheless, the application of COTS parts in cryo-vacuum is often very difficult and represents a technological challenge.
Cryostats are closed chambers that hinder the monitoring of materials, structures or systems installed therein. This paper presents a webcam-based measurement and monitoring system, which can operate under vacuum and cryogenic conditions to be mainly used in astrophysical applications. The system can be configured in two different assemblies: wide field that can be used for mechanism monitoring and narrow field, especially useful in cryogenic precision measurements with a resolution up to 4 microns/pixel.
HARMONI is a visible and near-infrared (0.47 to 2.45 μm) integral field spectrometer, providing the E-ELT's core
spectroscopic capability, over a range of resolving powers from R (≡λ/Δλ)~500 to R~20000. The instrument provides simultaneous spectra of ~32000 spaxels at visible and near-IR wavelengths, arranged in a √2:1 aspect ratio contiguous field. HARMONI is conceived as a workhorse instrument, addressing many of the E-ELT’s key science cases, and will
exploit the E-ELT's scientific potential in its early years, starting at first light. HARMONI provides a range of spatial
pixel (spaxel) scales and spectral resolving powers, which permit the user to optimally configure the instrument for a
wide range of science programs; from ultra-sensitive to diffraction limited, spatially resolved, physical (via morphology),
chemical (via abundances and line ratios) and kinematic (via line-of-sight velocities) studies of astrophysical sources.
Recently, the HARMONI design has undergone substantial changes due to significant modifications to the interface with
the telescope and the architecture of the E-ELT Nasmyth platform. We present an overview of the capabilities of
HARMONI, and of its design from a functional and performance viewpoint.
HARMONI is a visible and near-infrared (0.47μm to 2.5μm) integral field spectrometer providing the E-ELT's core
spectroscopic capability. It will provide ~32000 simultaneous spectra of a rectangular field of view at four foreseen
different spatial sample (spaxel) scales. The HARMONI fore-optics re-formats the native telescope plate scale to suitable
values for the downstream instrument optics. This telecentric adaptation includes anamorphic magnification of the plate
scale to optimize the performance of the IFU, which contains the image slicer, and their four spectrographs. In addition,
it provides an image of the telescope pupil to assemble a cold stop shared among all the scales allowing efficient
suppression of the thermal background. A pupil imaging unit also re-images the pupil cold stop onto the image slicer to
check the relative alignment between the E-ELT and HARMONI pupils. The scale changer will also host the filter wheel
with the long-pass filters to select the wavelength range. The main reasoning specifying the importance of the
HARMONI fore-optics and its current optical and mechanical design is described in this contribution.
In order to improve the signal-to-noise ratio of HARMONI (E-ELT first light visible and near-infrared integral field VIR
spectrometer), a pupil mask has been identified to be included at the fore-optics to limit the background radiation coming
into the spectrographs. This mask should rotate synchronously with the telescope pupil during observations, taking into
account the combined effects of the telescope tracking and the de-rotation of the FOV. The implementation of the pupil
mask functionality will require complex movements with high precision at cryogenic temperatures which implies an
important technological challenge.
This paper details a set of experiments completed to gain knowledge and experience in order to accomplish the design
and control of cryogenic mechanisms reaching this type of pupil motion. The conceptual design of the whole mechanism
started from the feedback acquired from those experiments is also described in the following sections.
OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy) was the optical Day One instrument
for the 10.4m Spanish telescope GTC. It is installed at the Observatorio del Roque de Los Muchachos (La Palma, Spain).
This instrument has been operational since March-2009 and covers from 360 to 1000 nm. OSIRIS observing modes
include direct imaging with tunable and conventional filters, long slit and low resolution spectroscopy. OSIRIS wide
field of view and high efficiency provide a powerful tool for the scientific exploitation of GTC. OSIRIS was developed
by a Consortium formed by the Instituto de Astrofísica de Canarias (IAC) and the Instituto de Astronomía de la
Universidad Nacional Autónoma de México (IA-UNAM). The latter was in charge of the optical design, the manufacture
of the camera and collaboration in the assembly, integration and verification process. The IAC was responsible for the
remaining design of the instrument and it was the project leader. The present paper considers the development of the
instrument from its design to its present situation in which is in used by the scientific community.
EST (European Solar Telescope) is a 4-m class solar telescope, which is currently in the conceptual design phase. EST
will be located in the Canary Islands and will aim at high spectral, spatial and temporal resolution observations in the
photosphere and chromosphere, using a suite of instruments that can produce efficiently two-dimensional
spectropolarimetric information of the thermal, dynamic and magnetic properties of the plasma over many scale heights.
The pier is defined as the construction that supports the telescope and the enclosure. It needs a certain height to minimize
daytime ground turbulence. At the bottom of the pier a large instrument lab is located, 16 m in diameter and 10 m high.
To the pier is attached a service building that accommodates all auxiliary services, possibly together with a separate
building.
Solid concrete- and open framework piers are compared, in terms of stability, thermal properties and flow characteristics
and building structures in terms of construction issues. FE and CFD analysis are used to give qualitative insight in the
differences between the alternatives. The preferred alternative is a cone shaped pier surrounded by an open framework.
KEYWORDS: Mirrors, Telescopes, Secondary tip-tilt mirrors, Actuators, Adaptive optics, Solar telescopes, Space telescopes, Deformable mirrors, Active optics, Signal attenuation
The European Solar Telescope (EST) is a European collaborative project to build a 4m class solar telescope in the
Canary Islands, which is now in its design study phase. The telescope will provide diffraction limited performance for
several instruments observing simultaneously at the Coudé focus at different wavelengths. A multi-conjugated adaptive
optics system composed of a tip-tilt mirror and several deformable mirrors will be integrated in the telescope optical
path.
The secondary mirror system is composed of the mirror itself (Ø800mm), the alignment drives and the cooling system
needed to remove the solar heat load from the mirror. During the design study the feasibility to provide fast tip-tilt
capabilities at the secondary mirror to work as the adaptive optics tip-tilt mirror is also being evaluated.
The Wind Evaluation Breadboard (WEB) for the European Extremely Large Telescope (ELT) is a primary mirror and
telescope simulator formed by seven segments simulators, including position sensors, electromechanical support systems
and support structures. The purpose of the WEB is to evaluate the performance of the control of wind buffeting
disturbance on ELT segmented mirrors using an electro-mechanical set-up which simulates the real operational
constrains applied to large segmented mirrors. The instrument has been designed and developed by IAC, ALTRAN,
JUPASA and ESO, with FOGALE responsible of the Edge Sensors, and TNO of the Position Actuators. This paper
describes the mechanical design and analysis, the control architecture, the dynamic model generated based on the Finite
Element Model and the close loop performance achieved in simulations. A comparison in control performance between
segments modal control and actuators local control is also presented.
We present in this paper the new cute-SCIDAR instrument, entirely developed by the Instituto de Astrofísica de Canarias
(IAC), delivered recently at the European Southern Observatory (ESO) Paranal Observatory (Chile). This instrument,
supported by the European Community (Framework Programme 6, Extremely Large Telescope Design Study), carries
out the generalized SCIntillation Detection And Ranging (g-SCIDAR) technique to obtain the temporal evolution of
turbulence profiles CN
2 with height. A new design was made in order to fit the VLT Auxiliary Telescopes (ATs)
interfaces and control requirements. Also, a new software architecture allows a full remote control, and a data analysis
pipeline provides turbulence profiles in real-time, which is the main achievement of this new cute-SCIDAR. Details of
its design and results of its excellent performance are included.
The European Extremely Large Telescope (E-ELT) is a 42-m class optical telescope with a segmented primary mirror
composed of 984 segments which is currently being studied by ESO (European Southern Observatory). The segment
support system combines a series of mechanical whiffletrees for the axial support, a central diaphragm for lateral support
and a torsional constrainer. These elements are fixed to a common moving frame which is actively moved by means of
three actuators in piston and tip-tilt in order to keep the whole primary mirror in phase. The moving frame is fixed to the
segments subcells, which properly attach the segments to the cell structure, by means of special flexures, allowing large
axial alignment capability combined with high lateral stiffness. This paper describes the development of the support
system for the primary mirror segments of the E-ELT, which has been specified for a high stiffness and
eigenfrequencies, 60Hz for axial modes and 40Hz for lateral ones.
This communication shows the design, layout, mounting and start-up of a high-resolution grating spectrograph for VIS-NIR
at GREGOR 1.5m Solar Telescope (Observatorio del Teide, Tenerife, Canary Islands). The instrument will be used
together with the Tenerife Infrared Polarimeter (TIP-II). As special characteristics of the design, the following can be
mentioned: The first folding mirror of the spectrograph can be placed in two positions to take into account the change of the
optical axis introduced by the polarizing beamsplitter of TIP-II. This way the instrument is optimally aligned when used
in situations with and without polarimeter. The second and third mirrors rotate the image of the entrance slit, making it parallel to the grating grooves. A system of prisms are used to adequately fit onto the detector the two orthogonal polarized beams generated by the
polarimeter. Two output beams are possible, to make feasible simultaneous visible and near-infrared observations.
New dispersive elements providing relative high resolution (R=2200) have been recently incorporated in the near
infrared spectrograph LIRIS. These elements are founded on a rather novel design based on a diffractive pattern
engraved in fused silica, which is placed between two prisms. These new components are pushing forward the scientific
capabilities of the instrument by enhancing the medium resolution spectroscopic mode of operation. Details on the
design, specifications and measured performances, as well as aspects related to the integration and astronomical tests in
the instrument are presented.
We have built a hybrid turbulence profiler measuring simultaneously the atmospheric turbulence structure with a Shack-
Hartmann wave front sensor and a G-SCIDAR (scintillation sensor). This is the first instrument combining two different
techniques to measure simultaneously the turbulence structure. The hybrid profiler has been installed at the Carlos
Sánchez Telescope (TCS) at the Teide Observatory (OT), in Tenerife Spain. The G-SCIDAR arm is already working
properly and we are still testing the Shack-Hartmann arm.
Large segmented mirrors require efficient co-phasing techniques in order to avoid the image degradation due to segments misalignment. For this purpose in the last few years new co-phasing techniques have been developed in collaboration with several European institutes. The Active Phasing Experiment (APE) will be a technical instrument aimed at testing different phasing techniques for an Extremely Large Telescope (ELT). A mirror composed of 61 hexagonal segments will be conjugated to the primary mirror of the VLT (Very Large Telescope). Each segment can be moved in piston, tip and tilt. Three new types of co-phasing sensors dedicated to the measurement of segmentation errors will be tested, evaluated and compared: ZEUS (Zernike Unit for Segment phasing) developed by LAM and IAC, PYPS (PYramid Phase Sensor) developed by INAF/ARCETRI, and DIPSI (Diffraction Image Phase Sensing Instrument) developed by IAC, GRANTECAN and LAM. This experiment will first run in the laboratory with point-like polychromatic sources and a turbulence generator. In a second step, it will be mounted at the Nasmyth platform focus of a VLT unit telescope. This paper describes the scientific concept of DIPSI, its optomechanical design, the signal analysis to retrieve segment piston and tip-tilt, the multiwavelength algorithm to increase the capture range, and the multiple segmentation case, including both simulation and laboratory tests results.
We describe the ZEUS phasing camera for future extremely large telescopes (ELTs) based on the Zernike phase contrast method. A prototype instrument is under construction for implementation in the Active Phasing Experiment (APE), a VLT test bed scheduled for operation in 2007. The paper describes theoretical aspects of the method and its experimental validation, as well as the instrumental implementation for APE. Aspects of its implementation in an ELT are also discussed. While the classical Zernike method uses a phase mask with diameter approximately equal to the Airy disk, we employ a mask the size of the seeing disk. This allows us to overcome the problems related to atmospheric turbulence, whose low spatial frequency phase errors are much larger than the co-phasing errors to be measured. The thickness (OPD) of the mask can be set to lambda/4 - as in the classical case - for maximum signal strength, but for initial phasing where phase errors are much larger than the sensor's linear range (+/-lambda/4), a thinner mask produces a cleaner signal more easily exploitable, leaving the signal analysis more robust. A multi wavelength approach is implemented in order to extend the capture range of the sensor, and the ultimate precision is reached using an iterative approach. End-to-end simulations indicating an achievable precision within the required precision will be shown.
In the planning stage of extremely large telescopes, site testing and study of high performance adaptive optics systems plays very important roles. Site testing is a very time consuming task, therefore, we have built a fully automatic device - the CUTE SCIDAR instrument with a user-friendly interface and real time processing. This instrument is already in operation and now has been installed in the Jacobus Kapteyn Telescope of Roque de los Muchachos Observatory at La Palma for periodical turbulence profiling.
A second version with an additional phase sensor bench contains a motorized field stop, a field lens, a collimator lens, and a Shack-Hartmann sensor. This instrument measures the turbulence from both amplitude and phase variations of the same distorted wave at high frequency bandwidth, with a high resolution and dynamic range. On the one hand, this will solve the calibration problem between different turbulence sensors. On the other hand, it allows investigating the performance of multi-conjugated wavefront sensing using real time information from SCIDAR data and proving validity of the near field assumption. From preliminary Shack-Hartmann measurements we conclude that the instrument should be flexible to change optical layout and detection parameters according to the turbulence conditions. Therefore, the phase sensor branch includes automatically controlled moveable devices, and in the future, fast communication facilities between control computers of both SCIDAR and wavefront sensing are previewed. In this paper, we will present our objectives of building such an instrument, give a detailed state of art design, and considerate the preparation of first observational campaigns, that are the first scientific tasks to do.
LIRIS is a near-infrared intermediate resolution spectrograph with added capabilities for multi-slit, imaging, coronography, and polarimetry, developed by the Instituto de Astrofisica de Canarias (IAC). It will be a common user instrument for the Cassegrain focus of the William Herschel Telescope (WHT) at the Roque de los Muchachos Observatory in La Palma. At its first commissioning, that was held in February 2003, the functionality of the mechanisms (entrance wheel, central wheels and camera wheel) under variable orientation of the telescope was verified, and no thermal nor structural problems arose. The functionality of the mechanical interface with telescope (allows for up to 5 mm of lateral displacements in the attachment plane), of the LIRIS handling trolley, of the transport equipment and of all the equipments used in the integration was also checked. For the second commissioning of LIRIS, which has been held in March 2004, some modifications have been done. The results of both commissionings were satisfactory.
LIRIS is a near-infrared (1-2.5 microns) intermediate resolution spectrograph (R=1000-3000) with added capabilities for multi-slit, imaging, coronography, and polarimetry, built by the IAC to be a common instrument for the WHT (La Palma). Here we report the results of the two commissioning periods. The image quality was checked, obtaining a FWHM of 0".5 in the Ks band over the whole field of view (4'.2 x 4'.2). Zero points and sky brightness were measured, and very low values were found in the latter. The long slit spectra obtained matched the expected spectral resolution (2.6 pixels for a 0".65-wide slit). Flexure tests were carried out with good results. Several science targets were observed, the most note-worthy result being the detection of the CIV 154.9 nm line in the most distant qso at z=6.41.
LIRIS is a near-infrared (0.9 - 2.4 microns) intermediate resolution spectrograph (R = 1000-3000) conceived as a common user instrument for the (WHT) at the Observatorio del Roque de los Muchachos (ORM) La Palma. LIRIS is now being assembled, integrated and virified at the Instituto Astrofisico de Canarias (IAC). LIRIS will have imaging, long-slit and multi-object spectroscopy working modes. Coronography and polarimetry capabilities will eventually be added. Image capability will allow easy target acquisition.
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