We present the results of our project for the design and construction and on-sky test of silicon
grisms. The fabrication of such devices is a complex and critical process involving litho-masking,
anisotropic etching and direct bonding techniques. After the successful fabrication of the silicon
grating, we have optimized the bonding of the grating onto the hypotenuse of a silicon prism to get
the final prototype. After some critical phases during the experimentation a silicon grism with 363
grooves/mm and a blaze angle of 14 degrees has been eventually fabricated. The application of an
A/R coating on both the surfaces has been the last step: this procedure is critical because of the
groove geometry of the diffraction grating, whose performace might be compromised by the
coating. Then, the grism was inserted in the filter wheel of the Near Infrared camera NICS, at the
focal plane of the National Galileo Telescope (TNG), the 3.5 m Italian facility in the Canary Islands
(E). The result of the on-sky tests are given in detail.
KEYWORDS: Sensors, Point spread functions, Diffraction, Spectrographs, Computer simulations, Zemax, Device simulation, Signal to noise ratio, Near infrared, Photon counting
MOONS will be the next near infrared fiber fed multi-object spectrograph for the Very Large Telescope, that will offer a
one thousand multiplexing capability and a simultaneous coverage of the wavelength range from 0.8 to 1.8 μm.
With the aim of quantitatively i) assessing the instrument performances with respect to sensitivity and OH subtraction, ii)
blind-testing the 1D spectra extraction and calibration, provided by the data reduction pipeline, and iii) testing the
technical solutions adopted for reaching the outstanding instrument requirements, we have developed “Virtual
MOONS”, an end-to-end software simulator, which quantitatively computes high fidelity focal plane raw images,
emulating the output of the detector electronics.
Starting from an ideal photon image derived from the geometrical optics propagation and Point Spread Function (PSF)
variations computed by the ZEMAX optical design, the end-to-end optical budget is introduced along with the stray light
contributions, resulting in the expected photon counts impinging the detector pixels. Then the photon image plus photon
noise is converted to digital counts by means of a detailed detector simulation, including pixel-to-pixel response
variation, dark, bias, read-out noise, cosmetics, charge diffusion, flatness and read-out schemes. Critical points like fiber
differential response, PSF haloes and sky emission variations have been also taken into account.
The current status of this work is presented with an example simulated image and numerical results.
MOONS is a new Multi-Object Optical and Near-infrared Spectrograph selected by ESO as a third generation
instrument for the Very Large Telescope (VLT). The grasp of the large collecting area offered by the VLT (8.2m
diameter), combined with the large multiplex and wavelength coverage (optical to near-IR: 0.8μm - 1.8μm) of MOONS
will provide the European astronomical community with a powerful, unique instrument able to pioneer a wide range of
Galactic, Extragalactic and Cosmological studies and provide crucial follow-up for major facilities such as Gaia,
VISTA, Euclid and LSST. MOONS has the observational power needed to unveil galaxy formation and evolution over
the entire history of the Universe, from stars in our Milky Way, through the redshift desert, and up to the epoch of very
first galaxies and re-ionization of the Universe at redshift z>8-9, just few million years after the Big Bang. On a
timescale of 5 years of observations, MOONS will provide high quality spectra for >3M stars in our Galaxy and the
local group, and for 1-2M galaxies at z>1 (SDSS-like survey), promising to revolutionise our understanding of the
Universe.
The baseline design consists of ~1000 fibers deployable over a field of view of ~500 square arcmin, the largest patrol
field offered by the Nasmyth focus at the VLT. The total wavelength coverage is 0.8μm-1.8μm and two resolution
modes: medium resolution and high resolution. In the medium resolution mode (R~4,000-6,000) the entire wavelength
range 0.8μm-1.8μm is observed simultaneously, while the high resolution mode covers simultaneously three selected
spectral regions: one around the CaII triplet (at R~8,000) to measure radial velocities, and two regions at R~20,000 one
in the J-band and one in the H-band, for detailed measurements of chemical abundances.
LINC-NIRVANA (LN) is the near-infrared, Fizeau-type imaging interferometer for the large binocular telescope (LBT) on Mt. Graham, Arizona (elevation of 3267 m). The instrument is currently being built by a consortium of German and Italian institutes under the leadership of the Max Planck Institute for Astronomy in Heidelberg, Germany. It will combine the radiation from both 8.4 m primary mirrors of LBT in such a way that the sensitivity of a 11.9 m telescope and the spatial resolution of a 22.8 m telescope will be obtained within a 10.5×10.5 arcsec 2 scientific field of view. Interferometric fringes of the combined beams are tracked in an oval field with diameters of 1 and 1.5 arcmin. In addition, both incoming beams are individually corrected by LN’s multiconjugate adaptive optics system to reduce atmospheric image distortion over a circular field of up to 6 arcmin in diameter. A comprehensive technical overview of the instrument is presented, comprising the detailed design of LN’s four major systems for interferometric imaging and fringe tracking, both in the near infrared range of 1 to 2.4 μm, as well as atmospheric turbulence correction at two altitudes, both in the visible range of 0.6 to 0.9 μm. The resulting performance capabilities and a short outlook of some of the major science goals will be presented. In addition, the roadmap for the related assembly, integration, and verification process are discussed. To avoid late interface-related risks, strategies for early hardware as well as software interactions with the telescope have been elaborated. The goal is to ship LN to the LBT in 2014.
LINC-NIRVANA (LN) is the near-infrared, Fizeau-type imaging interferometer for the Large Binocular Telescope
(LBT) on Mt. Graham, Arizona, USA (3267m of elevation). The instrument is currently being built by a consortium of
German and Italian institutes under the leadership of the Max Planck Institute for Astronomy (MPIA) in Heidelberg,
Germany. It will combine the radiation from both 8.4m primary mirrors of LBT in such a way that the sensitivity of a
11.9m telescope and the spatial resolution of a 22.8m telescope will be obtained within a 10.5arcsec x 10.5arcsec
scientific field of view. Interferometric fringes of the combined beams are tracked in an oval field with diameters of 1
and 1.5arcmin. In addition, both incoming beams are individually corrected by LN’s multi-conjugate adaptive optics
(MCAO) system to reduce atmospheric image distortion over a circular field of up to 6arcmin in diameter.
This paper gives a comprehensive technical overview of the instrument comprising the detailed design of LN’s four
major systems for interferometric imaging and fringe tracking, both in the NIR range of 1 - 2.4μm, as well as
atmospheric turbulence correction at two altitudes, both in the visible range of 0.6 - 0.9μm. The resulting performance
capabilities and a short outlook of some of the major science goals will be presented. In addition, the roadmap for the
related assembly, integration and verification (AIV) process will be discussed. To avoid late interface-related risks,
strategies for early hardware as well as software interactions with the telescope have been elaborated. The goal is to ship
LN to the LBT in 2014.
The possibility to open a near-IR window at stratospheric altitude is crucial for a large variety of astronomical issues,
from cosmology to the star formation processes. Up to now, one of the main issue is the role of the OH and thermal sky
emission that are rising the sky background level when such observations are performed through ground based
telescopes. We present the results of our technological activity aimed at affording some critical aspects typical of balloon
flights. In particular, the obtained performances of prototype systems for rough and fine tracking will be illustrated. Both
these systems constitute a high precision device (≤ 1 arcsec) for pointing and tracking light telescopes on board
stratospheric balloons. We give the details concerning the optical and mechanical layout, as well as the detector and the
control system. We demonstrate how such devices, when used at the focal plane of enough large telescopes(2-4m, F/10),
may be capable to provide diffraction limited images in the near infrared bands. We have also developed a prototypal
single channel photometer NISBA (Near Infrared Sky Background at Arctic pole), working in the H band (1.65 μm), able
to evaluate, during a high-latitude balloon flight, how OH emission affects the sky background during the arctic night.
The laboratory tests and performance on sky are presented and analyzed.
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.
MOONS is a new conceptual design for a Multi-Object Optical and Near-infrared Spectrograph for the Very Large
Telescope (VLT), selected by ESO for a Phase A study. The baseline design consists of ~1000 fibers deployable over a
field of view of ~500 square arcmin, the largest patrol field offered by the Nasmyth focus at the VLT. The total
wavelength coverage is 0.8μm-1.8μm and two resolution modes: medium resolution and high resolution. In the medium
resolution mode (R~4,000-6,000) the entire wavelength range 0.8μm-1.8μm is observed simultaneously, while the high
resolution mode covers simultaneously three selected spectral regions: one around the CaII triplet (at R~8,000) to
measure radial velocities, and two regions at R~20,000 one in the J-band and one in the H-band, for detailed
measurements of chemical abundances.
The grasp of the 8.2m Very Large Telescope (VLT) combined with the large multiplex and wavelength coverage of
MOONS – extending into the near-IR – will provide the observational power necessary to study galaxy formation and
evolution over the entire history of the Universe, from our Milky Way, through the redshift desert and up to the epoch
of re-ionization at z<8-9. At the same time, the high spectral resolution mode will allow astronomers to study chemical
abundances of stars in our Galaxy, in particular in the highly obscured regions of the Bulge, and provide the necessary
follow-up of the Gaia mission. Such characteristics and versatility make MOONS the long-awaited workhorse near-IR
MOS for the VLT, which will perfectly complement optical spectroscopy performed by FLAMES and VIMOS.
We report the results of a simulation and reconstruction of observations of a young stellar object (YSO) jet with the LINC-NIRVANA (LN) interferometric instrument, which will be mounted on the Large Binocular Telescope (LBT). This simulation has been performed in order to investigate the ability of observing the weak diffuse jet line emission against the strong IR stellar continuum through narrow band images in the H and K atmospheric windows. In general, this simulation provides clues on the image quality that could be achieved in observations with a high dynamic range. In these cases, standard deconvolution methods, such as Richardson-Lucy, do not provide satisfactory results: we therefore propose here a new method of image reconstruction. It consists in considering the image to be reconstructed as the sum of two terms: one corresponding to the star (whose position is assumed to be known) and the other to the jet. A regularization term is introduced for this second component and the reconstruction is obtained with an iterative method alternating between the two components. An analysis of the results shows that the image quality obtainable with this method is significantly improved with respect to standard deconvolution methods, reducing the number of artifacts and allowing us to reconstruct the original jet intensity distribution with an error smaller than 10%.
LINC-NIRVANA is the IR Fizeau interferometric imager that will be installed within a couple of years on the Large
Binocular Telescope (LBT) in Arizona. Here we present a particular sub-system, the so-called Patrol Camera (PC),
which has been now completed, along with the results of the laboratory tests. It images (in the range 600-900 nm) the
same 2 arcmin FoV seen by the Medium-High Wavefront Sensor (MHWS), adequately sampled to provide the MHWS
star enlargers with the positions of the FoV stars with an accuracy of 0.1 arcsec. To this aim a diffraction-limited
performance is not required, while a distortion free focal plane is needed to provide a suitable astrometric output. Two
identical systems have been realized, one for each single arm, which corresponds to each single telescope. We give here
the details concerning the optical and mechanical layout, as well as the CCD and the control system. The interfaces (mainly software procedures) with LINC-NIRVANA (L-N) are also presented.
KEYWORDS: Telescopes, Stars, Spectral resolution, Spatial resolution, Interferometry, Integrated optics, Space telescopes, Visibility, Image restoration, Signal to noise ratio
The VLTI Spectro Imager (VSI) was proposed as a second-generation instrument of the Very Large Telescope Interferometer
providing the ESO community with spectrally-resolved, near-infrared images at angular resolutions
down to 1.1 milliarcsecond and spectral resolutions up to R = 12000. Targets as faint as K = 13 will be imaged
without requiring a brighter nearby reference object; fainter targets can be accessed if a suitable reference is
available. The unique combination of high-dynamic-range imaging at high angular resolution and high spectral
resolution enables a scientific program which serves a broad user community and at the same time provides the
opportunity for breakthroughs in many areas of astrophysics. The high level specifications of the instrument are
derived from a detailed science case based on the capability to obtain, for the first time, milliarcsecond-resolution
images of a wide range of targets including: probing the initial conditions for planet formation in the AU-scale
environments of young stars; imaging convective cells and other phenomena on the surfaces of stars; mapping
the chemical and physical environments of evolved stars, stellar remnants, and stellar winds; and disentangling the central regions of active galactic nuclei and supermassive black holes. VSI will provide these new capabilities
using technologies which have been extensively tested in the past and VSI requires little in terms of new
infrastructure on the VLTI. At the same time, VSI will be able to make maximum use of new infrastructure as it
becomes available; for example, by combining 4, 6 and eventually 8 telescopes, enabling rapid imaging through
the measurement of up to 28 visibilities in every wavelength channel within a few minutes. The current studies
are focused on a 4-telescope version with an upgrade to a 6-telescope one. The instrument contains its own
fringe tracker and tip-tilt control in order to reduce the constraints on the VLTI infrastructure and maximize
the scientific return.
LINC-NIRVANA (LN) is a Fizeau interferometer that will provide for the first time coherent images in the near-IR combining the beams from the two Large Binocular Telescope (LBT)arms, by adopting a Multi-Coniugate
Adaptive Optics system (MCAO) that allows for atmospheric turbulence compensation. We applied a software
for the simulation and the reconstruction of LN images (AIRY-LN, see Desidera et al.1 this Conference) in two
specific scientific cases: a relatively distant galaxy at redshift about 1 and a collimated jet from a Young Stellar
Object (YSO). These two cases have been chosen to test the capability of LN in the observations of faint and
small (1-2 arcsec) extragalactic objects and objects with diffuse emission and high dynamical range, respectively.
A total of six images at different hour angles have been obtained for both cases. Using these simulated images, we
obtained the final reconstructed images using the software package AIRY-LN. These images have been analyzed
with the standard data reduction software (IRAF and IDL). Our analysis show that the reconstruction algorithm
is fundamental to obtain a good reproduction of the original flux and morphology while the optimal number of
iterations strongly depends on the scientific goal.
The VLTI Spectro Imager project aims to perform imaging with a temporal resolution of 1 night and with a maximum
angular resolution of 1 milliarcsecond, making best use of the Very Large Telescope Interferometer capabilities. To
fulfill the scientific goals (see Garcia et. al.), the system requirements are: a) combining 4 to 6 beams; b) working in
spectral bands J, H and K; c) spectral resolution from R= 100 to 12000; and d) internal fringe tracking on-axis, or off-axis
when associated to the PRIMA dual-beam facility.
The concept of VSI consists on 6 sub-systems: a common path distributing the light between the fringe tracker and the
scientific instrument, the fringe tracker ensuring the co-phasing of the array, the scientific instrument delivering the
interferometric observables and a calibration tool providing sources for internal alignment and interferometric
calibrations. The two remaining sub-systems are the control system and the observation support software dedicated to the
reduction of the interferometric data.
This paper presents the global concept of VSI science path including the common path, the scientific instrument and the
calibration tool. The scientific combination using a set of integrated optics multi-way beam combiners to provide high-stability
visibility and closure phase measurements are also described. Finally we will address the performance budget of
the global VSI instrument. The fringe tracker and scientific spectrograph will be shortly described.
We present the optical and cryo-mechanical solutions for the Spectrograph of VSI (VLTI Spectro-Imager), the second
generation near-infrared (J, H and K bands) interferometric instrument for the VLTI. The peculiarity of this spectrograph
is represented by the Integrated Optics (IO) beam-combiner, a small and delicate component which is located inside the
cryostat and makes VSI capable to coherently combine 4, 6 or even 8 telescopes. The optics have been specifically
designed to match the IO combiner output with the IR detector still preserving the needed spatial and spectral sampling,
as well as the required fringe spacing. A compact device that allows us to interchange spectral resolutions (from R=200
to R=12000), is also presented.
We present the results of our project aimed to design and construct silicon grisms. The fabrication of such devices is a
complex and critical process involving litho masking, anisotropic etching and direct bonding techniques. After the
successful fabrication of the silicon grating, we have optimized the bonding of the grating onto the hypotenuse of a
silicon prism to get the final prototype. After some critical phases during the experimentation a silicon grism has been
eventually fabricated with 363.6 grooves/mm and 14 degrees of blaze angle. The results of the cryo-optical laboratory
tests are reported, along with a general description of the adopted technological process. The positive results allows us to
offer to the international community a new capability in building such devices.
LINC-NIRVANA is the IR Fizeau interferometric imager of the Large Binocular Telescope (LBT) in Arizona.
Here we describe in particular the design, realization and preliminary tests of the so-called Patrol Camera. It
can image (in the range 600-900 nm) the same 2 arcmin FoV seen by the Medium- High-Wavefront Sensor
(MHWS), adequately sampled to provide the MHWS star enlargers with the positions of the FoV stars with
an accuracy of 0.1 arcsec. To this aim a diffraction-limited performance is not required, while a distortion free
focal plane is needed to provide a suitable astrometric output. Two identical systems will be realized, one for
each single arm, which corresponds to each single telescope. We give here the details concerning the optical
and mechanical design, as well as the CCD and the control system. The interfaces with LINC-NIRVANA are
also presented both in terms of matching the carbon fiber optical bench and developing of suitable software
procedures. Since the major components have been already gathered, the laboratory tests and the integration
are currently in progress.
LINC-NIRVANA is an infrared camera that will work in Fizeau interferometric way at the Large Binocular Telescope (LBT). The two beams that will be combined in the camera are corrected by an MCAO system, aiming to cancel the turbulence in a scientific field of view of 2 arcminutes. The MCAO wavefront sensors will be two for each arm, with the task to sense the atmosphere at two different altitudes (the ground one and a second height variable between a few kilometers and a maximum of 15 kilometers). The first wavefront sensor, namely the Ground layer Wavefront sensor (GWS), will drive the secondary adaptive mirror of LBT, while the second wavefront sensor, namely the Mid High layer Wavefront Sensor (MHWS) will drive a commercial deformable mirror which will also have the possibility to be conjugated to the same altitude of the correspondent wavefront sensor. The entire system is of course duplicated for the two telescopes, and is based on the Multiple Field of View (MFoV) Layer Oriented (LO) technique, having thus different FoV to select the suitable references for the two wavefront sensor: the GWS will use the light of an annular field of view from 2 to 6 arcminutes, while the MHWS will use the central 2 arcminutes part of the FoV. After LINC-NIRVANA has accomplished the final design review, we describe the MFoV wavefront sensing system together with its current status.
We describe the procedures adopted to realize the fiber unit for feeding the near IR multi-object spectrometer GOHSS. Since a scarce literature is available on this subject, all the steps of the fabrication processes are explained and documented through a detailed illustrative material: in particular the polishing methods of the fiber ends are addressed along with the criteria for evaluating the achieved results; the preparation and application of the ferrules; the matching with the input micro-lens; finally, the laboratory tests to measure the focal ratio degradation of each fiber are presented aiming also to certify the quality of the realized device.
The raw images coming from infrared multi-echelle fiber spectrographs are quite complex to be processed, extracted and calibrated. Available procedures are in general not exhaustive or assume high knowledge of command line environments. For the instrument GOHSS, a fiber-fed high resolution NIR spectrograph to be mounted at the Italian National Telescope TNG, we have, therefore, developed GO-CART (GOhss Calibration and Reduction Tool), a tool which automatically performs the whole stage from the assessment of the master instrument calibrations up to the final sky subtracted scientific spectra, by following predefined or user written pipelines, in which an error propagation analysis is envisaged at each step of the process. GO-CART joins together the powerful graphical and imaging capabilities of IDL with the worldwide acknowledged performances of the IRAF spectra extraction packages within an easy-to-use environment. It is fully configurable to be used with different instruments and can work on any platform on which IDL and IRAF can run. A smart data organization and proper file naming rules allow for a convenient management of any final or intermediate result. GO-CART also provides specific capabilities to model and subtract scattered light from highly packed echelle images and a custom optimal matching algorithm to perform residual-free OH subtraction.
We describe the current status and technical aspects of the GOHSS (Galileo OH Subtracted Spectrograph) project. Here we point out the most critical items and how we have implemented innovative technical solutions to fulfill the compelling requirements imposed by both the optical tolerances and the demands of a high sensitivity. In particular we examine the camera lens mechanics realized in ultra low expansion quartz; the refrigerator system; the IR array mount realized in an unconventional way; the effort put in procuring optical devices with quite large efficiencies. We are also developing the data reduction package along with the instrument simulator: the optimized procedures and the results on the visibility function of galaxies are given as well. Currently the instrument is in the integration phase at the laboratories of the Astronomical Observatory of Rome and the commissioning phase at the telescope is expected to start at the beginning of year 2003.
We report 3-5 μm infrared spectroscopy obtained with VLT-ISAAC on several protostellar jets. Together with H2 emission lines from the υ=1 rotovibrational state, the spectra show several pure rotational lines of the fundamental state with excitation temperature up to ~22000 K. These observations represent the first detection from the ground of pure rotational (υ=0) H2 lines in jets. We show how theoretical rotation diagrams indicate these lines as unique both to probe the presence of collisionally excited gas in NLTE conditions and to infer the gas density.
Silicon grisms are suitable optical devices that allow for a spectroscopic mode able to effectively complement the natural
imaging mode of IR cameras, providing high spectral resolution
(R>5000) in the near infrared. We present a review of the fabrication process aimed to produce IR grisms with high refractive index. Such devices are intended to implement a high resolution mode in the Near IR Camera-Spectrograph, NICS, the user instrument at the focal plane of the Italian national telescope Galileo. Litho masking and anisotropic etching techniques have been employed to get, firstly, silicon gratings of suitable size for astronomical use, then warm bonding techniques have been used to obtain the final grisms in echelle configuration. The results and the problems encountered in the bonding procedure are presented along with a future implementation of silicon grisms in space instrumentation.
Silicon grisms are very attractive as devices for IR spectroscopy in terms of high resolving power and compactness, necessary for many astronomical applications and for implementation of spectroscopic modes in large telescopes respectively. We present the fabrication process of a silicon grism as composed by an IR transmission grating coupled to a silicon prism. The silicon gratings were manufactured using silicon micromachining techniques, as electron beam lithography and wet anisotropic etching, achieving good uniformity over all the large surface (32 X 32 mm2) and grating facets of excellent optical quality; the final grism was realized by means of direct bonding of the grating onto the prism face. The results of laboratory tests on the first prototype are presented.
We describe the current status of the technical aspects of the GOHSS project. It consists of a fiber-fed NIR spectrograph for faint objects. It will be a second-light instrument for the Nasmyth focus of the 3.5m Galileo telescope located on La Palma. GOHSS is an innovative instrument which accomplishes OH night-sky subtraction, differently from the hardware solution used by other devices; it provides a multiechelle design with software OH subtraction capable of yielding about 25 spectra in the z,J and H bands at an effective spectral resolution of about 4000, which is necessary to strongly reduce the impact of atmospheric OH lines. The GOHSS design is completed and the operative phase is already started through the procurement of the most important components. We have also started to develop the data reduction package for the instrument and the first result of the 1D approach as presented.
We present the first results of a fabrication process aimed to produce IR grisms with high refractive index. Such devices are intended to implement a high resolution mode in the near IR camera-spectrograph, a user instrument at the focal plane of the Italian national telescope Galileo. Litho masking and anisotropic etching techniques have been employed to get, firstly, silicon gratings of suitable size for astronomical use, then warm bonding techniques will be used to obtain the final grisms in echelle configuration. The results of the laboratory test on the first prototype are presented.
We present the main characteristics and astronomical results of SWIRCAM, a NIR imager-spectrometer mainly devoted to the search for extragalactic Supernovae, in the frame of the SWIRT project, a joint scientific collaboration among the Astronomical Observatories of Rome, Teramo and Pulkovo. The camera is currently at the focal plane of the AZT-24 1.1 m telescope at the Observing Station of Campo Imperatore, operated by the Astronomical Observatory of Rome. SWIRCAM saw its first light during December 1998 and it is currently employed for both the SWIRT operative phase and other institutional projects.
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