The NISP (Near Infrared Spectrometer and Photometer) is one of the two Euclid instruments (see ref [1]). It operates in the near-IR spectral region (950-2020nm) as a photometer and spectrometer. The instrument is composed of: - a cold (135K) optomechanical subsystem consisting of a Silicon carbide structure, an optical assembly, a filter wheel mechanism, a grism wheel mechanism, a calibration unit and a thermal control system - a detection system based on a mosaic of 16 H2RG with their front-end readout electronic. - a warm electronic system (290K) composed of a data processing / detector control unit and of an instrument control unit that interfaces with the spacecraft via a 1553 bus for command and control and via Spacewire links for science data This paper presents: - the final architecture of the flight model instrument and subsystems - the performances and the ground calibration measurement done at NISP level and at Euclid Payload Module level at operational cold temperature.
The Euclid mission objective is to understand why the expansion of the Universe is accelerating through by mapping the geometry of the dark Universe
by investigating the distance-redshift relationship and tracing the evolution of cosmic structures. The Euclid project is part of ESA's Cosmic Vision
program with its launch planned for 2020 (ref [1]).
The NISP (Near Infrared Spectrometer and Photometer) is one of the two Euclid instruments and is operating in the near-IR spectral region (900-
2000nm) as a photometer and spectrometer. The instrument is composed of:
- a cold (135K) optomechanical subsystem consisting of a Silicon carbide structure, an optical assembly (corrector and camera lens), a filter wheel
mechanism, a grism wheel mechanism, a calibration unit and a thermal control system
- a detection subsystem based on a mosaic of 16 HAWAII2RG cooled to 95K with their front-end readout electronic cooled to 140K, integrated on a
mechanical focal plane structure made with molybdenum and aluminum. The detection subsystem is mounted on the optomechanical subsystem
structure
- a warm electronic subsystem (280K) composed of a data processing / detector control unit and of an instrument control unit that interfaces with the
spacecraft via a 1553 bus for command and control and via Spacewire links for science data
This presentation describes the architecture of the instrument at the end of the phase C (Detailed Design Review), the expected performance, the
technological key challenges and preliminary test results obtained for different NISP subsystem breadboards and for the NISP Structural and Thermal
model (STM).
KEYWORDS: Data processing, Sensors, Near infrared, Spectrographs, Photometry, Data processing, Signal detection, Detection and tracking algorithms, Spectroscopy, Space operations, Image compression
The Near Infrared Spectrograph and Photometer (NISP) is one of the two instruments on board the EUCLID mission now under implementation phase; VIS, the Visible Imager is the second instrument working on the same shared optical beam. The NISP focal plane is based on a detector mosaic deploying 16x, 2048x2048 pixels^2 HAWAII-II HgCdTe detectors, now in advanced delivery phase from Teledyne Imaging Scientific (TIS), and will provide NIR imaging in three bands (Y, J, H) plus slit-less spectroscopy in the range 0.9÷2.0 micron. All the NISP observational modes will be supported by different parametrization of the classic multi-accumulation IR detector readout mode covering the specific needs for spectroscopic, photometric and calibration exposures. Due to the large number of deployed detectors and to the limited satellite telemetry available to ground, a consistent part of the data processing, conventionally performed off-line, will be accomplished on board, in parallel with the flow of data acquisitions. This has led to the development of a specific on-board, HW/SW, data processing pipeline, and to the design of computationally performing control electronics, suited to cope with the time constraints of the NISP acquisition sequences during the sky survey. In this paper we present the architecture of the NISP on-board processing system, directly interfaced to the SIDECAR ASICs system managing the detector focal plane, and the implementation of the on-board pipe-line allowing all the basic operations of input frame averaging, final frame interpolation and data-volume compression before ground down-link.
Aqueye+ is a new ultrafast optical single photon counter, based on single photon avalanche photodiodes (SPAD) and a 4- fold split-pupil concept. It is a completely revisited version of its predecessor, Aqueye, successfully mounted at the 182 cm Copernicus telescope in Asiago. Here we will present the new technological features implemented on Aqueye+, namely a state of the art timing system, a dedicated and optimized optical train, a high sensitivity and high frame rate field camera and remote control, which will give Aqueye plus much superior performances with respect to its predecessor, unparalleled by any other existing fast photometer. The instrument will host also an optical vorticity module to achieve high performance astronomical coronography and a real time acquisition of atmospheric seeing unit. The present paper describes the instrument and its first performances.
KEYWORDS: Data processing, Sensors, Data acquisition, Clocks, Control systems, Power supplies, Electronics, Interfaces, Photometry, Field programmable gate arrays
In this paper we describe the status of the development of the Data Processing Unit (DPU) of the Near-Infrared Spectro- Photometer (NISP) of the Euclid mission. The architecture of this unit is described, along with the Detector Control Unit (DCU), which operates the 16 HAWAII-2RG (H2RG), composing the NISP Focal Plane Array (FPA), by an equivalent number of SIDECAR systems. The design is evolved from the previous phases, with the implementation of a different approach in the data processing and consequently with the implementation of a large data buffer. The approach in implementing failure tolerance on this unit is described in detail; effort has been made to realize an architecture in which the impact of a single failure can be limited, in the worst case, to the loss of only one detector (out of 16). The main requirements driving the design are also described, in order to emphasize the most challenging areas and the foreseen solutions. The foreseen implementation of the on-board processing pipeline is also described, along with the basic interactions with the Instrument Control Unit (ICU) and with the Mass Memory Unit (MMU). Finally, we outline the on going activity for DPU/DCU bread-boarding.
Space missions, as EChO, or ground based experiments, as SPHERE, have been proposed to measure the atmospheric transmission, reflection and emission spectra. In particular, EChO is foreseen to probe exoplanetary atmospheres over a wavelength range from 0.4 to 16 micron by measuring the combined spectra of the star, its transmission through the planet atmosphere and the emission of the planet. The planet atmosphere characteristics and possible biosignatures will be inferred by studying such composite spectrum in order to identify the emission/absorption lines/bands from atmospheric molecules such as water (H2O), carbon monoxide (CO), methane (CH4), ammonia (NH3) etc. The interpretation of the future EChO observations depends upon the understanding of how the planet atmosphere affects the stellar spectrum and how this last affects the planet emission/absorption. In particular, it is important to know in detail the optical characteristics of gases in the typical physical conditions of the planetary atmospheres and how those characteristics could be affected by radiation induced phenomena such as photochemical and biological one. Insights in this direction can be achieved from laboratory studies of simulated planetary atmosphere of different pressure and temperature conditions under the effects of radiation sources, used as proxies of different bands of the stellar emission.
The Euclid mission objective is to understand why the expansion of the Universe is accelerating by mapping the geometry of the dark Universe by
investigating the distance-redshift relationship and tracing the evolution of cosmic structures. The Euclid project is part of ESA's Cosmic Vision
program with its launch planned for 2020.
The NISP (Near Infrared Spectro-Photometer) is one of the two Euclid instruments and is operating in the near-IR spectral region (0.9-2μm) as a
photometer and spectrometer. The instrument is composed of:
- a cold (135K) optomechanical subsystem consisting of a SiC structure, an optical assembly (corrector and camera lens), a filter wheel mechanism, a
grism wheel mechanism, a calibration unit and a thermal control system
- a detection subsystem based on a mosaic of 16 Teledyne HAWAII2RG cooled to 95K with their front-end readout electronic cooled to 140K,
integrated on a mechanical focal plane structure made with Molybdenum and Aluminum. The detection subsystem is mounted on the optomechanical
subsystem structure
- a warm electronic subsystem (280K) composed of a data processing / detector control unit and of an instrument control unit that interfaces with the
spacecraft via a 1553 bus for command and control and via Spacewire links for science data
This presentation describes the architecture of the instrument at the end of the phase B (Preliminary Design Review), the expected performance, the
technological key challenges and preliminary test results obtained on a detection system demonstration model.
The EChO Exoplanet Atmosphere Characterization mission will have in the midst of its main targets, planets that orbit M stars in their or very close to their habitable zone. In this framework at the Astronomical Observatory of Padova (INAF) we are going to perform experiments that will give us an idea about the possible modification of the atmosphere by photosynthetic biota present on the planet surface. In the framework of the project "Atmosphere In a Test Tube", planetary environmental conditions are being performed. The bacteria that are being studied are Acaryochloris marina, Chroococcidiopsis sp., Cyanidium Caldarium and Halomicronema hongdechloris and tests are being performed with LISA ambient simulator in the laboratory of the Padova Astronomical Observatory.
MOONS is a new conceptual design for a multi-object spectrograph for the ESO Very Large Telescope (VLT)
which will provide the ESO astronomical community with a powerful, unique instrument able to serve a wide
range of Galactic, Extragalactic and Cosmological studies. The instrument foresees 1000 fibers which can be
positioned on a field of view of 500 square-arcmin. The sky-projected diameter of each fiber is at least 1 arcsec
and the wavelengths coverage extends from 0.8 to 1.8 μm.
This paper presents and discusses the design of the spectrometer, a task which is allocated to the Italian National
Institute of Astrophysics (INAF).
The baseline design consists of two identical cryogenic spectrographs. Each instrument collects the light from
over 500 fibers and feeds, through dichroics, 3 spectrometers covering the "I" (0.79-0.94 μm), "YJ" (0.94-1.35
μm) and "H" (1.45-1.81 μm) bands.
The low resolution mode provides a complete spectrum with a resolving power ranging from R'4,000 in the
YJ-band, to R'6,000 in the H-band and R'8,000 in the I-band. A higher resolution mode with R'20,000 is
also included. It simultaneously covers two selected spectral regions within the J and H bands.
The Near Infrared Spectrograph and Photometer (NISP) is one of the instruments on board the EUCLID mission.
The focal plane array (FPA) consists of 16 HAWAII-2RG HgCdTe detectors from Teledyne Imaging Scientific
(TIS), for NIR imaging in three bands (Y, J, H) and slitless spectroscopy in the range 0.9−2µm. Low total noise
measurements (i.e. total noise < 8 electrons) are achieved by operating the detectors in multiple non-destructive
readout mode for the implementation of both the Fowler and Up-The-Ramp (UTR) sampling, which also enables
the detection and removal of cosmic ray events. The large area of the NISP FPA and the limited satellite telemetry
available impose to perform the required data processing on board, during the observations. This requires a well
optimized on-board data processing pipeline, and high-performance control electronics, suited to cope with the
time constraints of the NISP acquisition sequences. This paper describes the architecture of the NISP on-board
electronics, which take charge of several tasks, including the driving of each individual HAWAII-2RG detectors
through their SIDECAR ASICs, the data processing, inclusive of compression and storage, and the instrument
control tasks. We describe the implementation of the processing power needed for the demanding on-board data
reduction. We also describe the basic operational modes that will be managed by the system during the mission,
along with data flow and the Telemetry/TeleCommands flow. This paper reports the NISP on-board electronics
architecture status at the end of the Phase B1, and it is presented on behalf of the Euclid Consortium.
KEYWORDS: Sensors, Computer simulations, Spectroscopy, Nondestructive evaluation, Signal processing, Data modeling, Image compression, Photometry, Data processing, Data compression
NISP is the near IR spectrophotometer instrument part of the Cosmic Vision Euclid mission. In this paper we describe an
end-to-end simulation scheme developed in the framework of the NISP design study to cover the expected focal-plane
on-board pre-processing operations. Non-destructive detector readouts are simulated for a number of different readout
strategies, taking into account scientific and calibration observations; resulting frames are passed through a series of
steps emulating the foreseen on-board pipeline, then compressed to give the final result. In order to verify final frame
quality and resulting computational and memory load, we tested this architecture on a number of hardware platforms
similar to those possible for the final NISP computing unit. Here we give the results of the latest tests. This paper mainly
reports the technical status at the end of the Definition Phase and it is presented on behalf of the Euclid Consortium.
KEYWORDS: Sensors, Digital micromirror devices, Spectrographs, Head, Silicon carbide, Near infrared, Space telescopes, Cameras, Telescopes, Control systems
The ENIS wide-field spectrograph is part of the instrument package on board of the European space mission Euclid
devoted to map the dark universe and proposed for launch in 2017. ENIS will operate in the near-IR spectral region
(0.8-2 μm) and will provide in 4-5 years an accurate and extremely large survey of cosmological redshifts. The
instrument focal-plane is based on a combination of state of the art detectors light fed by a slitless spectrograph
allowing coverage and analysis of a high number of targets per cycle. During the feasibility study a spectrograph
option based on Digital Micromirror Device (DMD) programmable slits, allowing a significant increase in
instrumental sensitivity and accuracy, has also been examined. ENIS has been recently (Feb this year) pre-selected
for a phase-A study within a group of three medium class missions; final selection is foreseen for the end of next
year after a new phase of instrument revision.
A description of the work done during the feasibility-study phase for the ENIS focal-plane is here presented.
An autonomous observatory is being installed at Dome C in Antarctica. It will be constituted by the International
Robotic Antarctic Infrared Telescope (IRAIT) and the Antarctic Multiband Infrared CAmera (AMICA). Because of the
extreme environment, the whole system has been developed to operate robotically, paying particular attention to the
environmental conditions and the subsystems activity monitoring. A detailed description of the IRAIT/AMICA data
acquisition process and management will be shown, focusing on automated procedures and solutions against safety risks.
AMICA is a double-armed camera designed to perform NIR/ MIR (2-28 μm) Astronomy from Antarctica. It will be
installed at Dome C in 2010-2011. An overview of the instrument is given, with attention to the following features: 1)
Winterization: AMICA has been tested under Antarctic conditions to be operated in severe environments; 2) Automation:
AMICA does not require human intervention; 3) Fast acquisition: AMICA can get images with exposure times less than
3 msec; 4) Survey-mode observations: the low background in Antarctica allows AMICA to have FOVs of 2.29 arcmin
(NIR) and 2.89 arcmin (MIR), without saturation even with wide-band filters.
AMICA (Antarctic Medium Infrared Camera) [1] is the imaging camera that will support first-light testing for the IRAIT
telescope.
IRAIT (International Robotic Antarctic Infrared Telescope) is a 80 cm class telescope to be installed at Dome C, a site
located at 3200m height on the Antarctic plateau. AMICA, placed at the telescope Nasmyth focus, is a dual feed infrared
camera: a medium infrared optical beam designed to be operated by a Si:As detector array covering the range 5-28 μm,
and a near infrared optical beam operated by a In:Sb detector array covering the spectral range down to J band. A
specific goal of this project, having to face the prohibitive Antarctic environment imposing strong limits to human and
equipments operation, is the need to implement robotic and remotely controlled procedures for the telescope and its
instrumentation. This will impose well integrated and cooperative control systems, besides the accurate insulation for all
the equipment exposed to the extreme environmental conditions of Dome C (T -90, p 640 mbar).
In the present paper we will provide an overview of the progress so far obtained in the construction and testing of the
AMICA control system.
The IRAIT project is aimed at preparing the first permanent observatory, a 80 cm class telescope, at Dome C, a site located at 3200 height on the Antarctic plateau. To exploit the high-quality and low-sky-background conditions offered by the site in spectral regions beyond 20 μm, IRAIT telescope will be equipped at its Nasmyth focus by a dual feed infrared camera: a near/medium infrared camera (AMICA) designed to be operated by a Si:As detector array sensitivity in the range 5-28 μm, and a In:Sb detector array covering the shorter spectral range down to J band. AMICA is a joint effort of several Italian institutions (OAMI, OATO, OAPD) led by the Teramo Observatory, belonging to Istituto Nazionale di Astrofisica (INAF). The importance of this instrument is twofold: AMICA is expected to provide extensive surveys of the southern sky in K,L,M,N and Q bands, and to give a direct estimate of the observational quality of this highly promising site. To face the prohibitive Antarctic environment, the telescope should be fully robotic and operations for the telescope and its instrumentation remotely controlled. Careful consideration is to be devoted to the design and integration of the control system, besides the accurate insulation for all the equipment. In the present paper we will provide an overview of the AMICA camera focused on the detectors control electronics, the solutions adopted to reduce the impact with a severe environment and the present status of the project.
The Antarctic Plateau offers unique opportunities for ground-based Infrared Astronomy. AMICA (Antarctic Multiband Infrared CAmera) is an instrument designed to perform astronomical imaging from Dome-C in the near- (1 - 5 μm) and mid- (5 - 27 μm) infrared wavelength regions. The camera consists of two channels, equipped with a Raytheon InSb 256 array detector and a DRS MF-128 Si:As IBC array detector, cryocooled at 35 and 7 K respectively. Cryogenic devices will move a filter wheel and a sliding mirror, used to feed alternatively the two detectors. Fast control and readout, synchronized with the chopping secondary mirror of the telescope, will be required because of the large background expected at these wavelengths, especially beyond 10 μm. An environmental control system is needed to ensure the correct start-up, shut-down and housekeeping of the camera. The main technical challenge is represented by the extreme environmental conditions of Dome C (T about -90 °C, p around 640 mbar) and the need for a complete automatization of the overall system. AMICA will be mounted at the Nasmyth focus of the 80 cm IRAIT telescope and will perform survey-mode automatic observations of selected regions of the Southern sky. The first goal will be a direct estimate of the observational quality of this new highly promising site for Infrared Astronomy. In addition, IRAIT, equipped with AMICA, is expected to provide a significant improvement in the knowledge of fundamental astrophysical processes, such as the late stages of stellar evolution (especially AGB and post-AGB stars) and the star formation.
Thanks to exceptional coldness, low sky brightness and low content of water vapour of the above atmosphere Dome C,
one of the three highest peaks of the large Antarctic plateau, is likely to be the best site on Earth for thermal infrared
observations (2.3-300 μm) as well as for the far infrared range (30 μm-1mm). IRAIT (International Robotic Antarctic
Infrared Telescope) will be the first European Infrared telescope operating at Dome C. It will be delivered to Antarctica
at the end of 2006, will reach Dome C at the end of 2007 and the first winter-over operation will start in spring 2008.
IRAIT will offer a unique opportunity for astronomers to test and verify the astronomical quality of the site and it will be
a useful test-instrument for a new generation of Antarctic telescopes and focal plane instrumentations. We give here a
general overview of the project and of the logistics and transportation options adopted to facilitate the installation of
IRAIT at Dome C. We summarize the results of the electrical, electronics and networking tests and of the sky
polarization measurements carried out at Dome C during the 2005-2006 summer-campaign. We also present the 25 cm
optical telescope (small-IRAIT project) that will installed at Dome C during the Antarctic summer 2006-2007 and that
will start observations during the 2007 Antarctic winter when a member of the IRAIT collaboration will join the Italian-French Dome C winter-over team.
We present a calibration unit to be used in near and medium infrared instrumentation. The system belongs to the 'black-body' (BB) and 'integrating-sphere' (IS) category and has been developed during the phase-A study as part of the Medium Infrared Instrument (MIRI) to be inserted on the NASA-ESA mission James Webb Space Telescope (JWST). A voltage driven resistance temperature device (RTD) is used as active thermal light source with spectral energy distribution determined by the working temperature and material characteristics, while the integrating sphere is used in order to create a Lambertian beam of calibration light. The system would provide light both for flat-fielding calibration and, in a further development, for wavelength calibration making use of the same illumination optics.
We will describe the experimental setup and the properties requested by the device. A complete analytical simulation guiding the dimensioning of the emitter and IS is given with the results from several laboratory test made in order to qualify the system in realistic operating conditions.
The AdOptTNG module is an adaptive optics facility permanently mounted at the Nasmyth focus of the 4m-class Telescopio Nazionale Galileo (TNG). Its integration on the telescope started in late November 1998 and first-light of the speckle and tip-tilt modes took place shortly after. Both modes have been offered to the astronomical community and turned out to provide performances close to the expectations. Double stars with separation below 0.1 arcsec have been resolved by the speckle facility. Improvement of the Strehl ratio of a factor two and enhancement in the FWHM from 0.65 arcsec to 0.35 arcsec have been obtained on relatively faint reference stars. The high-speed low noise CCD, namely an 80 X 80 pixel read from the four corners, has been mounted and aligned with the Shack-Hartmann wavefront sensor. A Xinetics mirror with 96 actuators has been calibrated against the wavefront sensor with on-board alignment fibers. This has been done using a modal approach and using Singular Value Decomposition in order to get a reliable interaction matrix. Filtering can be modal too, using a default integrative filter coupled with a limited FIR-fashioned technique. Open loop measurements on the sky provide data to establish open loop transfer functions and realistic estimates of limiting magnitude. High-order wavefront correction loop has been successfully tested on the sky. In this paper we give a description of the overall functionality of the module and of the procedure required to acquire targets to be used as reference in the correction. A brief overview of the very first astronomical results obtained so far on angular size and shape measurements of a few asteroids and sub-arcsec imaging of Planetary Nebulae and Herbig Haro objects is also given.
KEYWORDS: Telescopes, Computer programming, Control systems, Optical alignment, Active optics, Cameras, Mirrors, Electroluminescence, Information science, Computing systems
The commissioning phase of the Telescopio Nazionale Galileo is started during the first half of 97. Large parts of the drive, the optical and the control system have been mounted at the telescope in site (LaPalma, Canary Islands). The telescope is expected to be ready for the technical first- light during February - March 98 while the instrumentation first-light is expected for mid 98. On this review of the commissioning operations we will describe the problems encountered and the results achieved integrating the main telescope subsystems.
AdOpt@TNG is the Adaptive Optics module for the Italian “Telescopio Nazionale Galileo" (TNG), a 4m? class telescope that will have its first light in late 1997. This module incorporates a number of peculiar features such as the adoption of an electro-magnetically driven tip-tilt mirror, a continuously adjustable offset between the reference and the scientific objects (in a way to deal, for instance, with moving references, like asteroids, or targets, like comets), a built-in speckle camera with an on-line autocorrelator and others. The speckle camera has been tested at the 1.82m telescope of the Astronomical Observatory of Asiago, a short account of the results obtained is given. Most of the elements of the AdOpt@TNG module have been manufactured and tested. The up-to-date status report of the module is briefly given.
The status report of the adaptive optics module for the 3.5 m TNG telescope is briefly given together with the description of three important subsystems: the off-axis tracking capability of the wavefront sensor; the CCD to be used for the wavefront sensor and the modal filtering approach to be implemented in the module.
In the last years, the Charge Coupled Device (CCD) detectors have had a great development: 2048 X 2048 pixel formats are routinely produced by silicon foundries with good electro- optical characteristics. Scientific CCDs now, not only offer the ability to be read from more than one output, but they can also be buttable to form mosaics in order to cover a larger field of view, requirement posed by the current telescope technology. The Italian National Telescope GALILEO (TNG) will support a large set of visual and near IR detectors dedicated to scientific measurements at the focal plane. Also tracking systems and Shack-Hartmann wavefront analyzers will be based on CCD technology. Due to the number of camera systems to be routinely operated, the possibility to have uniformed interaction and configuration of systems is emerged as an important requirement for this crucial part of the telescope. In this paper the detector and instrument plan foreseen for the TNG telescope will be presented on the first part, while on the second we will present the CCD controller, now at the end of development. Here presented is a modular system based on digital signal processors and transputer modules. It is interfaced to host computers (PCs, workstations or VME crates) via optical fibers and a specially developed VME-VSB interface board.
KEYWORDS: Control systems, Telescopes, Actuators, Astronomy, Computer architecture, Observatories, Computer programming, Global Positioning System, Local area networks, Telecommunications
TNG first light is foreseen for the latter half of 1996. Due to its main characteristics (alt- azimuthal mounting with tight pointing and tracking requirements, deformable primary mirror with active control, actively controlled secondary and tertiary mirrors), the computer support is essential, together with the need to command instrumentation and the possibility to operate remotely. Most of the control system has been developed and is now under test phase. The main characteristics of the computing environment are presented here. The implications of the desired performances on pointing and tracking are discussed and solutions to define the time base and synchronization are proposed.
The Project Telescopio Nazionale GALILEO (TNG) will provide a 3.5-m telescope for the Italian astronomical community. Its main features closely parallel those of the ESO New Technology Telescope (NNT). We describe here its characteristics and its most important differences with respect to the NTT. The figuring of the three mirrors was successfully completed, with results exceeding the specifications. The telescope structure has been assembled in the workshop, and alignment tests are under way. The control system (motors, encoders, VME and workstation environment) is also in an advanced stage of development. The TNG will be part of the Observatorio del Roque de los Muchachos, in the Canary Islands. Its location is on the West side of the mountain, some 400-m from the NOT; excavation works are already well advanced. Civil works should be finished in the course of the current year. It is expected to complete the rotating building, and the erection of the telescope before the end of 1995, to start regular operations in 1996.
A large part of the active optics system and control environment for the Galileo telescope has been developed and tested. Presently the primary mirror support cell has been characterized for the mechanical and optical aspects. The primary mirror has also been characterized and tested with the active support system in work. Part of the mechanics for the secondary and tertiary active mirror supports has been constructed and we plan to start the characterization work in the second half of this year. An overview of the main results obtained during factory acceptance tests and a discussion about the general informatics implementation is here provided.
The Italian GALILEO telescope (TNG) is in an advanced phase of construction. Among the various
new technical aspects of this telescope the active optics system is now receiving special consideration.
In particular, the optical and informatic groups are considering the definition of the control
environment dedicated to the active-optics.
A solution based on an array of interconnected l6bit transputers is here described with the main
requirements for the inter-communication and monitoring software.
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