FRIDA (inFRared Imager and Dissector for Adaptive optics) is a near-infrared integral-field spectrograph operating at the wavelength range of 0.9 to 2.5 μm for use at the Nasmyth B platform of the Gran Telescopio de Canarias (GTC). FRIDA is a collaborative project led by the Instituto de Astronomía Universidad Nacional Autónoma de México (IA-UNAM, México) with the collaboration of the Instituto de Astrofísica de Canarias (IAC, Spain), Centro de Ingeniería y Desarrollo Industrial (CIDESI, México), the University of Florida (UF, USA), and the Universidad Complutense de Madrid (UCM, Spain). In imaging mode, FRIDA will provide scales of 0.010, 0.020, and 0.040 arc sec / pixel and, in IFS mode, spectral resolutions of R ∼ 1000, 4500, and 30,000. FRIDA is the first GTC instrument to use the telescope’s adaptive optics (GTCAO) system and is rescheduled to be delivered to the GTC shortly in 2020. This paper not only provides a starting point for possible future developers of GTC instruments but also presents a generic solution that we adopted in FRIDA to manage the sequences of operations and science observations. Specifically, this paper gives an overview of the high-level control software components of FRIDA. The main components are the mechanisms control system, whose primary task is to control the mechanisms of FRIDA, the data acquisition system, which interacts with the detector to take images, the data factory system, whose main tasks are to perform the reduction, storage and also to provide quality control for both engineering and scientific data, the Instrument Library (IL) component responsible for operating the devices associated with FRIDA, and the sequencer manager component responsible for the execution of both the operational sequencing of the telescope’s instruments and the observing sequences of FRIDA in close co-ordination with the GTCAO system. In other GCS instruments, the responsibilities of the sequencer manager are inside the IL representing an overload on this component with the added problems of extensibility and reusability.
The instrument FRIDA (inFRared Imager and Dissector for Adaptive optics) is an integral field spectrograph (near infrared) operating at the wavelength range of 0.9 to 2.5um with imaging capability for being used at the Nasmyth B platform of the Gran Telescopio de Canarias (GTC). FRIDA is a collaborative project led by the Instituto de Astronomía Universidad Nacional Autónoma de México (IA-UNAM, México) with the collaboration of the Instituto de Astrofísica de Canarias (IAC, Spain), Centro de Ingeniería y Desarrollo Industrial (CIDESI, México), the University of Florida (UF, USA), and the Universidad Complutense de Madrid (UCM, Spain). In imaging mode, FRIDA will provide scales of 0.010, 0.020 and 0.040 arcsec/pixel and, in IFS mode, spectral resolutions of R 1000, 4.500 and 30.000. FRIDA is the first GTC instrument to use the telescope Adaptive Optic (AO) system and it is rescheduled to be delivered to GTC shortly in 2020. Since FRIDA is a GTC instrument, the high-level control software of FRIDA is embedded within the distributed architecture of the System Control of GTC (GCS) and must fulfill the GCS software and hardware standards to control the telescope and the AO system. This paper shows an overview of the high-level control software components of FRIDA inside the GCS architecture. The main components are the Mechanisms Control System whose primary task is to control the mechanisms of FRIDA, the Data Acquisition System that interacts with the detector to take image, the Data Factory Agent whose task is to provide quality control for both engineering and scientific data, the Instrument Library component responsible for operating the devices associated to FRIDA and the Observation Manager component responsible for the execution of the observing sequences in close coordination with the GTC AO system.
The instrument FRIDA (inFRared Imager and Dissector for Adaptive optics) is an integral field spectrograph (near infrared) with imaging capability for being used at the Nasmyth B platform of the Gran Telescopio de Canarias (GTC), behind the Adaptive Optics (AO) system. FRIDA is the first GTC instrument to use the telescope AO system. FRIDA is a collaborative project between institutions from México, Spain and the USA. In image mode, FRIDA provides scales of 0.010, 0.020 and 0.040 arcsec/pixel and, in integral-field spectroscopy (IFS) mode, spectral resolutions R 1000, 4.500 and 30.000. FRIDA has a set of different mechanisms (such as the focal plane wheel, the filters and pupil wheels, the cameras wheel, the calibration unit, the grating carousel) that are controlled and coordinated by the FRIDA Instrument Library (IL). In this paper, we present the IL, which provides the implementation of a Device that represents the instrument FRIDA as a whole. More specifically, the IL implements the commands for setting-up and coordinating the different mechanisms of FRIDA for an observation. It moves the mechanisms, exposes the detector, and reduces and stores the data image. In addition, we also present the Observation Manager (OM) component, responsible for the execution of the science observing sequences in close coordination with the IL and GTC AO system.
FRIDA is a diffraction-limited imager and integral-field spectrometer that is being built for the adaptive-optics focus of the Gran Telescopio Canarias. In imaging mode FRIDA will provide scales of 0.010, 0.020 and 0.040 arcsec/pixel and in IFS mode spectral resolutions of 1500, 4000 and 30,000. FRIDA is starting systems integration and is scheduled to complete fully integrated system tests at the laboratory by the end of 2017 and to be delivered to GTC shortly thereafter. In this contribution we present a summary of its design, fabrication, current status and potential scientific applications.
FRIDA is a diffraction limited imager and integral field spectrometer that is being built for the Gran Telescopio
Canarias. FRIDA has been designed and is being built as a collaborative project between institutions from México, Spain
and the USA. In imaging mode FRIDA will provide scales of 0.010, 0.020 and 0.040 arcsec/pixel and in IFS mode
spectral resolutions R ~ 1000, 4,500 and 30,000. FRIDA is starting systems integration and is scheduled to complete
fully integrated system tests at the laboratory by the end of 2015 and be delivered to GTC shortly after. In this
contribution we present a summary of its design, fabrication, current status and potential scientific applications.
FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) is designed as
a diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy capabilities
with low (R ~ 1,500), intermediate (R ~ 4,500) and high (R ~ 30,000) spectral resolutions to operate in the wavelength
range 0.9 - 2.5 μm. The integral field unit is based on a monolithic image slicer. The imaging and IFS observing modes
will use the same Teledyne 2K x 2K detector. FRIDA will be based at the Nasmyth B platform of GTC, behind the AO
system. The key scientific objectives of the instrument include studies of solar system bodies, low mass objects,
circumstellar outflow phenomena in advanced stages of stellar evolution, active galactic nuclei, high redshift galaxies,
resolved stellar populations, semi-detached binary systems, young stellar objects and star forming environments. FRIDA
is a collaborative project between the main GTC partners, namely, Spain, México and Florida. In this paper, we present
the status of the instrument design as it is currently being prepared for its manufacture, after an intensive prototypes'
phase and design optimization. The CDR was held in September 2011.
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.
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 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 (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.
The instrument LIRIS is a near IR spectrograph to be installed at the
WHT telescope. Currently it is being assembled at the Instituto de Astrofisica de Canarias. The instrument will have a Hawaii 1Kx1K array as the detector. Here we report the laboratory characterization of the scientific grade unit. We give the
relevant parameters such as linearity range, gain and readout noise. These results confirm that the science grade detector will fulfil the astronomical requirements for making LIRIS a front line IR instrument. We also discuss some peculiar effects which need
to be taken into account in order to guarantee a correct astronomical performance. Among these effects we consider: variation of the dark signal with integration time, cross-talk, and persistance. We also discuss the variation of the bias level with detector temperature and the need to establish an extremely stable control of the temperature.
LIRIS is a near-IR intermediate resolution spectrograph with added capabilities for multi-object, imaging, coronography, and polarimetry. This instrument is now being constructed at the IAC, and upon complexion will be installed on the 4.2m William Herschel Telescope at the Observatorio del Roque de Los Muchachos. The optical system uses lenses and is based on a classical collimator/camera design. Grisms are used as the dispersion elements. The plate scale matches the median seeing at the ORM. The detector is a Hawaii 1024 X 1024 HgCdTe array operating at 60K.
The imaging photopolarimeter ISOPHOT on-board the European satellite ISO houses 144 background detectors of Si:Ga, Si:P, Ge:Ga and stressed Ge:Ga, all sampled by newly developed cold read-out electronics. There is large temporal radiation damage to most of these detectors on the daily passage through the earth's radiation belts. In addition the Ge:Ga detectors exhibit a continuous responsivity increase caused by the cosmic radiation far off the earth. Effective curing procedure shave been developed to heat out these effects. The in-flight sensitivities achieved are close to the pre-flight predictions for most channels. At 100-200 micrometers cirrus confusion is a serious limit for the detection of faint objects on large parts of the sky. The cold filter wheel carrying 56 optical elements, such as filters, apertures and polarizers, as well as the focal plane chopper, operate with high precision and very low power consumption. Due to an effective cold internal baffle system the measured near-field straylight was close to the pre- flight theoretical prediction based on APART simulations. THe sun and moon straylight at 25 and 175 micrometers was measured during several solar eclipses. Drift and transients of the detectors, non-linearities of the preamplifiers, ionizing radiation effects and a complex optical path make the photometric calibration of this instrument challenging. Because most of these effects are reproducible, a calibration accuracy of < 30 percent is already available for most photometric modes. Examples of observations, including the 175 micrometers Serendipitous Sky Survey, will highlight the capabilities of the instrument.
The Instituto de Astrofisica de Canarias (IAC) is undertaking the construction of an IR camera for astronomical use at the 1.5 meter (f/13,8) Carlos Sanchez IR Telescope (CST), sited at the Observatorio del Teide (Tenerife). The camera will employ a 256 X 256 InSb focal plane array, and will be used in the 1 - 5 micron atmospheric windows. The Camera uses an optical reimaging system which maps 0.5 square arcseconds of sky per pixel. The optical system will be diamond turned in aluminum and mounted in such a way that the optical alignment is facilitated. Two filter wheels will accommodate 14 broad and narrow band filters. A SUN SPARCstation will control the camera and allow data handling and displaying of the images. With this configuration we expect to achieve sensitivities of 17 and 12.5 magnitude (3 (sigma) in 10 sec) at the K and L band respectively.