The Lunar Ultraviolet Observatory (OUL) is a small instrument designed to map the Earth exosphere, the magnetosphere and the near-Earth space while orbiting the Moon. It can operate either as a flight-alone cubesat mission or as an instrument. The observatory is a small space telescope to be set in Lunar orbit to produce wide field images (10x10 deg2) in narrow and broad bands in the 115-175 nm spectral range. In this presentation, we will describe the results of the on-going tests of critical optical elements.
The Large Millimeter Telescope (LMT) Alfonso Serrano is a bi-national (Mexico and USA) telescope facility constructed on the summit of Sierra Negra, at an altitude of 4600m, in the Mexican state of Puebla. The LMT is a 50-m diameter single-dish telescope, with an active surface control-system to correct gravitational and thermal deformations of the primary reflector, designed and optimized to conduct scientific observations using heterodyne and continuum receivers, as well as VLBI observations, at frequencies between ~70 and 350 GHz. We describe the current status and technical performance of the recently commissioned LMT 50-m, the instrumentation development program, and future engineering upgrades that will optimize the optical efficiency of the telescope and increase its scientific productivity.
The Large Millimeter Telescope Alfonso Serrano (LMT) is a 50m-diameter radio telescope for millimeter-wave astronomy. In this paper we describe a number of initiatives underway to upgrade the antenna systems and permit scientific observations during daylight hours. We summarize recent efforts to characterize the thermal gradients that occur within the LMT structure and to identify important modes of surface deformation. The mitigation program involves use of the LMT's active surface to counteract the effects of measured thermal gradients within the antenna structure. It also includes active measures such as the installation of a ventilation system in the antenna backup structure. Prospects for additional active metrology measurements of the antenna surface for real-time surface corrections are also discussed.
The Large Millimeter Telescope (LMT) Alfonso Serrano is a 50m-diameter single-dish radio telescope constructed at an altitude of 4600 meters on the summit of Volcan Sierra Negra, an extinct volcano in the Mexican state of Puebla. The LMT is a bi-national scientific collaboration between Mexico and the USA, led by the Instituto Nacional de Astrofisica, Optica y Electronica (INAOE) and the University of Massachusetts at Amherst. The telescope currently operates at wavelengths from 4mm to 1mm, and during the dry winter months the LMT site provides the highest levels of atmospheric transmission and potential future access to submillimeter observing windows. This paper describes the current status and scientific performance of the LMT, the suite of scientific instrumentation and future engineering upgrades that will optimize the optical efficiency of the telescope and increase its scientific productivity.
TolTEC is a three-band imaging polarimeter for the Large Millimeter Telescope. Simultaneously observing with passbands at 1.1mm, 1.4mm and 2.0mm, TolTEC has diffraction-limited beams with FWHM of 5, 7, and 11 arcsec, respectively. Over the coming decade, TolTEC will perform a combination of PI-led and Open-access Legacy Survey projects. Herein we provide an overview of the instrument and give the first quantitative measures of its performance in the lab prior to shipping to the telescope in 2021.
The mm-wavelength sky reveals the initial phase of structure formation, at all spatial scales, over the entire observable history of the Universe. Over the past 20 years, advances in mm-wavelength detectors and camera systems have allowed the field to take enormous strides forward – particularly in the study of the Cosmic Microwave Background – but limitations in mapping speeds, sensitivity and resolution have plagued studies of astrophysical phenomena. In fact, limitations due to inherent biases in the ground-based mm-wavelength surveys conducted over the last 2 decades continue to motivate the need for deeper and wider-area maps made with increased angular resolution. TolTEC is a new camera that will fill the focal plane of the 50m diameter Large Millimeter Telescope (LMT) and provide simultaneous, polarization-sensitive imaging at 2.0, 1.4, and 1.1mm wavelengths. The instrument, now under construction, is a cryogenically cooled receiver housing three separate kilo-pixel arrays of Kinetic Inductance Detectors (KIDs) that are coupled to the telescope through a series of silicon lenses and dichroic splitters. TolTEC will be installed and commissioned on the LMT in early 2019 where it will become both a facility instrument and also perform a series of 100 hour “Legacy Surveys” whose data will be publicly available. The initial four surveys in this series: the Clouds to Cores Legacy Survey, the Fields in Filaments Legacy Survey, the Ultra-Deep Legacy Survey and the Large Scale Structure Survey are currently being defined in public working groups of astronomers coordinated by TolTEC Science Team members. Data collection for these surveys will begin in late 2019 with data releases planned for late 2020 and 2021. Herein we describe the instrument concept, provide performance data for key subsystems, and provide an overview of the science, schedule and plans for the initial four Legacy Survey concepts.
The Large Millimeter Telescope (LMT) Alfonso Serrano is a bi-national (Mexico and USA) telescope facility operated by the Instituto Nacional de Astrofisica, Optica y Electronica (INAOE) and the University of Massachusetts. The LMT is designed as a 50-m diameter single-dish millimeter-wavelength telescope that is optimized to conduct scientific observations at frequencies between ~70 and 350 GHz. The LMT is constructed on the summit of Sierra Negra at an altitude of 4600m in the Mexican state of Puebla. The site offers excellent mm-wavelength atmospheric transparency all-year round, and the opportunity to conduct submillimeter wavelength observations during the winter months. Following first-light observations in mid-2011, the LMT began regular scientific operations in 2014 with a shared-risk Early Science observing program using the inner 32-m diameter of the primary reflector with an active surface control system. The LMT has already performed successful VLBI observations at 3mm with the High Sensitivity Array and also at 1.3mm as part of the Event Horizon Telescope. Since early 2018 the LMT has begun full scientific operations as a 50-m diameter telescope, making the LMT 50-m the world´s largest single-dish telescope operating at 1.1mm. I will describe the current status of the telescope project, including the early scientific results from the LMT 50-m, as well the instrumentation development program, the plan to improve the overall performance of the telescope, and the on-going transition towards the formation of the LMT Observatory to support the scientific community in their use of the LMT to study the formation and evolution of structure at all cosmic epochs.
E. Carrasco, A. Gil de Paz, J. Gallego, J. Iglesias-Páramo, R. Cedazo, M. L. García Vargas, X. Arrillaga, J. L. Avilés, A. Bouquin, J. Carbajo, N. Cardiel, M. A. Carrera, A. Castillo Morales, E. Castillo-Domínguez, S. Esteban San Román, D. Ferrusca, P. Gómez-Álvarez, R. Izazaga-Pérez, B. Lefort, J. A. López Orozco, M. Maldonado, I. Martínez Delgado, I. Morales Durán, E. Mújica, R. Ortiz, G. Páez, S. Pascual, A. Pérez-Calpena, P. Picazo, A. Sánchez-Penim, E. Sánchez-Blanco, S. Tulloch, M. Velázquez, J. Vílchez, J. Zamorano, A. Aguerri, D. Barrado, E. Bertone, A. Cava, C. Catalán-Torrecilla, J. Cenarro, M. Chávez, B. Dullo, C. Eliche, Mi. García, J. García-Rojas, J. Guichard, R. González-Delgado, R. Guzmán, A. Herrero, N. Huélamo, D. Hughes, J. Jiménez-Vicente, C. Kehrig, R. Marino, I. Márquez, J. Masegosa, D. Mayya, J. Méndez-Abreu, M. Mollá, C. Muñoz-Tuñón, M. Peimbert, P. Pérez-González, E. Pérez-Montero, S. Roca-Fàbrega, M. Rodríguez, J. M. Rodríguez-Espinosa, L. Rodríguez-Merino, L. Rodríguez-Muñoz, D. Rosa-González, J. Sánchez-Almeida, C. Sánchez Contreras, P. Sánchez-Blázquez, S. Sánchez, A. Sarajedini, S. Silich, S. Simón-Díaz, G. Tenorio-Tagle , E. Terlevich, R. Terlevich, S. Torres-Peimbert, I. Trujillo, Y. Tsamis, O. Vega
MEGARA is the new generation IFU and MOS optical spectrograph built for the 10.4m Gran Telescopio CANARIAS (GTC). The project was developed by a consortium led by UCM (Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain) and UPM (Spain). The instrument arrived to GTC on March 28th 2017 and was successfully integrated and commissioned at the telescope from May to August 2017. During the on-sky commissioning we demonstrated that MEGARA is a powerful and robust instrument that provides on-sky intermediate-to-high spectral resolutions RFWHM ~ 6,000, 12,000 and 20,000 at an unprecedented efficiency for these resolving powers in both its IFU and MOS modes. The IFU covers 12.5 x 11.3 arcsec2 while the MOS mode allows observing up to 92 objects in a region of 3.5 x 3.5 arcmin2. In this paper we describe the instrument main subsystems, including the Folded-Cassegrain unit, the fiber link, the spectrograph, the cryostat, the detector and the control subsystems, and its performance numbers obtained during commissioning where the fulfillment of the instrument requirements is demonstrated.
A. Gil de Paz, E. Carrasco, J. Gallego, J. Iglesias-Páramo, R. Cedazo, M. L. García-Vargas, X. Arrillaga, J. Avilés, A. Bouquin, J. Carbajo, N. Cardiel, M. Carrera, A. Castillo-Morales, E. Castillo-Domínguez, S. Esteban San Román, D. Ferrusca, P. Gómez-Álvarez, R. Izazaga-Pérez, B. Lefort, J. López-Orozco, M. Maldonado, I. Martínez-Delgado, I. Morales-Durán, E. Mujica, G. Páez, S. Pascual, A. Pérez-Calpena, P. Picazo, A. Sánchez-Penim, E. Sánchez-Blanco, S. Tulloch, M. Velázquez, J. Vílchez, J. Zamorano, A. Aguerri, D. Barrado y Navascues, S. Berlanas, E. Bertone, A. Cava, C. Catalán-Torrecilla, J. Cenarro, M. Chávez, B. Dullo, M. García, J. García-Rojas, J. Guichard, R. González-Delgado, R. Guzmán, A. Herrero, N. Huélamo, D. Hughes, J. Jiménez-Vicente, C. Kehrig, R. Marino, I. Márquez, J. Masegosa, D. Mayya, J. Méndez-Abreu, M. Mollá, C. Muñoz-Tuñón, M. Peimbert, P. Pérez-González, E. Pérez-Montero, M. Rodríguez, J. Rodríguez-Espinosa, L. Rodríguez Merino, L. Rodríguez-Muñoz, D. Rosa-González, J. Sánchez-Almeida, C. Sánchez-Contreras, P. Sánchez-Blázquez, S. Sánchez, A. Sarajedini, S. Silich, S. Simón-Díaz, G. Tenorio-Tagle, E. Terlevich, R. Terlevich, S. Torres-Peimbert, I. Trujillo, Y. Tsamis, O. Vega
On June 25th 2017, the new intermediate-resolution optical IFU and MOS of the 10.4-m GTC had its first light. As part of the tests carried out to verify the performance of the instrument in its two modes (IFU and MOS) and 18 spectral setups (identical number of VPHs with resolutions R=6000-20000 from 0.36 to 1 micron) a number of astronomical objects were observed. These observations show that MEGARA@GTC is called to fill a niche of high-throughput, intermediateresolution IFU and MOS observations of extremely-faint narrow-lined objects. Lyman-α absorbers, star-forming dwarfs or even weak absorptions in stellar spectra in our Galaxy or in the Local Group can now be explored to a new level. Thus, the versatility of MEGARA in terms of observing modes and spectral resolution and coverage will allow GTC to go beyond current observational limits in either depth or precision for all these objects. The results to be presented in this talk clearly demonstrate the potential of MEGARA in this regard.
We describe a potential prototype of modern spectrometer based on acousto-optical technique with three parallel optical arms for analysis of radio-wave signals specific to astronomical observations. Each optical arm exhibits original performances to provide parallel multi-band observations with different scales simultaneously. Similar multi-band instrument is able to realize measurements within various scenarios from planetary atmospheres to attractive objects in the distant Universe. The arrangement under development has two novelties. First, each optical arm represents an individual spectrum analyzer with its individual performances. Such an approach is conditioned by exploiting various materials for acousto-optical cells operating within various regimes, frequency ranges, and light wavelengths from independent light sources. Individually produced beam shapers give both the needed incident light polarization and the required apodization for light beam to increase the dynamic range of the system as a whole. After parallel acousto-optical processing, a few data flows from these optical arms are united by the joint CCD matrix on the stage of the combined extremely high-bit rate electronic data processing that provides the system performances as well. The other novelty consists in the usage of various materials for designing wide-aperture acousto-optical cells exhibiting the best performances within each of optical arms. Here, one can mention specifically selected cuts of tellurium dioxide, bastron, and lithium niobate, which overlap selected areas within the frequency range from 40 MHz to 2.0 GHz. Thus one yields the united versatile instrument for comprehensive studies of astronomical objects simultaneously with precise synchronization in various frequency ranges.
We develop a multi-band spectrometer with a few spatially parallel optical arms for the combined processing of their
data flow. Such multi-band capability has various applications in astrophysical scenarios at different scales: from objects
in the distant universe to planetary atmospheres in the Solar system. Each optical arm exhibits original performances to
provide parallel multi-band observations with different scales simultaneously. Similar possibility is based on designing
each optical arm individually via exploiting different materials for acousto-optical cells operating within various
regimes, frequency ranges and light wavelengths from independent light sources. Individual beam shapers provide both
the needed incident light polarization and the required apodization to increase the dynamic range of a system. After
parallel acousto-optical processing, data flows are united by the joint CCD matrix on the stage of the combined
electronic data processing. At the moment, the prototype combines still three bands, i.e. includes three spatial optical
arms. The first low-frequency arm operates at the central frequencies ~60-80 MHz with frequency bandwidth ~40 MHz.
The second arm is oriented to middle-frequencies ~350-500 MHz with frequency bandwidth ~200-300 MHz. The third
arm is intended for ultra-high-frequency radio-wave signals about 1.0-1.5 GHz with frequency bandwidth <300 MHz.
To-day, this spectrometer has the following preliminary performances. The first arm exhibits frequency resolution ~20
KHz; while the second and third arms give the resolution ~150-200 KHz. The numbers of resolvable spots are 1500-
2000 depending on the regime of operation. The fourth optical arm at the frequency range ~3.5 GHz is currently under
construction.
A. Gil de Paz, E. Carrasco, J. Gallego, J. Iglesias-Páramo, R. Cedazo, M. L. García Vargas, X. Arrillaga, J. L. Avilés, N. Cardiel, M. A. Carrera, A. Castillo-Morales, E. Castillo-Domínguez, J. de la Cruz García, S. Esteban San Román, D. Ferrusca, P. Gómez-Álvarez, R. Izazaga-Pérez, B. Lefort, J. A. López-Orozco, M. Maldonado, I. Martínez-Delgado, I. Morales Durán, E. Mujica, G. Páez, S. Pascual, A. Pérez-Calpena, P. Picazo, A. Sánchez-Penim, E. Sánchez-Blanco, S. Tulloch, M. Velázquez, J. Vílchez, J. Zamorano, A. Aguerri, D. Barrado y Naváscues, E. Bertone, A. Cava, J. Cenarro, M. Chávez, M. García, J. García-Rojas, J. Guichard, R. González-Delgado, R. Guzmán, A. Herrero, N. Huélamo, D. Hughes, J. Jiménez-Vicente, C. Kehrig, R. Marino, I. Márquez, J. Masegosa, Y. Mayya, J. Méndez-Abreu, M. Mollá, C. Muñoz-Tuñón, M. Peimbert, P. Pérez-González, E. Pérez Montero, M. Rodríguez, J. Rodríguez-Espinosa, L. Rodríguez-Merino, L. Rodríguez-Muñoz, D. Rosa-González, J. Sánchez-Almeida, C. Sánchez Contreras, P. Sánchez-Blázquez, F. M. Sánchez Moreno, S. Sánchez, A. Sarajedini, S. Silich, S. Simón-Díaz, G. Tenorio-Tagle, E. Terlevich, R. Terlevich, S. Torres-Peimbert, I. Trujillo, Y. Tsamis, O. Vega
MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is an optical Integral-Field Unit (IFU) and Multi-Object Spectrograph (MOS) designed for the GTC 10.4m telescope in La Palma that is being built by a Consortium led by UCM (Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain), and UPM (Spain). The instrument is currently finishing AIV and will be sent to GTC on November 2016 for its on-sky commissioning on April 2017. The MEGARA IFU fiber bundle (LCB) covers 12.5x11.3 arcsec2 with a spaxel size of 0.62 arcsec while the MEGARA MOS mode allows observing up to 92 objects in a region of 3.5x3.5 arcmin2 around the IFU. The IFU and MOS modes of MEGARA will provide identical intermediate-to-high spectral resolutions (RFWHM~6,000, 12,000 and 18,700, respectively for the low-, mid- and high-resolution Volume Phase Holographic gratings) in the range 3700-9800ÅÅ. An x-y mechanism placed at the pseudo-slit position allows (1) exchanging between the two observing modes and (2) focusing the spectrograph for each VPH setup. The spectrograph is a collimator-camera system that has a total of 11 VPHs simultaneously available (out of the 18 VPHs designed and being built) that are placed in the pupil by means of a wheel and an insertion mechanism. The custom-made cryostat hosts a 4kx4k 15-μm CCD. The unique characteristics of MEGARA in terms of throughput and versatility and the unsurpassed collecting are of GTC make of this instrument the most efficient tool to date to analyze astrophysical objects at intermediate spectral resolutions. In these proceedings we present a summary of the instrument characteristics and the results from the AIV phase. All subsystems have been successfully integrated and the system-level AIV phase is progressing as expected.
A. Gil de Paz, J. Gallego, E. Carrasco, J. Iglesias-Páramo, R. Cedazo, J. Vílchez, M. García-Vargas, X. Arrillaga, M. Carrera, A. Castillo-Morales, E. Castillo-Domínguez, M. Eliche-Moral, D. Ferrusca, E. González-Guardia, B. Lefort, M. Maldonado, R. Marino, I. Martínez-Delgado, I. Morales Durán, E. Mujica, G. Páez, S. Pascual, A. Pérez-Calpena, A. Sánchez-Penim, E. Sánchez-Blanco, S. Tulloch, M. Velázquez, J. Zamorano, A. Aguerri, D. Barrado y Naváscues, E. Bertone, N. Cardiel, A. Cava, J. Cenarro, M. Chávez, M. García, J. Guichard, R. Gúzman, A. Herrero, N. Huélamo, D. Hughes, J. Jiménez-Vicente, C. Kehrig, I. Márquez, J. Masegosa, Y. Mayya, J. Méndez-Abreu, M. Mollá, C. Muñoz-Tuñón, M. Peimbert, P. Pérez-González, E. Pérez Montero, M. Rodríguez, J. Rodríguez-Espinosa, L. Rodríguez-Merino, D. Rosa-González, J. Sánchez-Almeida, C. Sánchez Contreras, P. Sánchez-Blázquez, F. Sánchez Moreno, S. Sánchez, A. Sarajedini, F. Serena, S. Silich, S. Simón-Díaz, G. Tenorio-Tagle, E. Terlevich, R. Terlevich, S. Torres-Peimbert, I. Trujillo, Y. Tsamis, O. Vega, V. Villar
MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is an optical Integral-Field Unit (IFU)
and Multi-Object Spectrograph (MOS) designed for the GTC 10.4m telescope in La Palma. MEGARA offers two IFU
fiber bundles, one covering 12.5x11.3 arcsec2 with a spaxel size of 0.62 arcsec (Large Compact Bundle; LCB) and
another one covering 8.5x6.7 arcsec2 with a spaxel size of 0.42 arcsec (Small Compact Bundle; SCB). The MEGARA
MOS mode will allow observing up to 100 objects in a region of 3.5x3.5 arcmin2 around the two IFU bundles.
Both the LCB IFU and MOS capabilities of MEGARA will provide intermediate-to-high spectral resolutions
(RFWHM~6,000, 12,000 and 18,700, respectively for the low-, mid- and high-resolution Volume Phase Holographic
gratings) in the range 3650-9700ÅÅ. These values become RFWHM~7,000, 13,500, and 21,500 when the SCB is used.
A mechanism placed at the pseudo-slit position allows exchanging the three observing modes and also acts as focusing
mechanism. The spectrograph is a collimator-camera system that has a total of 11 VPHs simultaneously available (out of
the 18 VPHs designed and being built) that are placed in the pupil by means of a wheel and an insertion mechanism. The
custom-made cryostat hosts an E2V231-84 4kx4k CCD.
The UCM (Spain) leads the MEGARA Consortium that also includes INAOE (Mexico), IAA-CSIC (Spain), and UPM
(Spain). MEGARA is being developed under a contract between GRANTECAN and UCM. The detailed design,
construction and AIV phases are now funded and the instrument should be delivered to GTC before the end of 2016.
A. Gil de Paz, E. Carrasco , J. Gallego , F. Sánchez , J. Vílchez Medina, M. L. García-Vargas, X. Arrillaga, M. A. Carrera, A. Castillo-Morales, E. Castillo-Domínguez, R. Cedazo, C. Eliche-Moral, D. Ferrusca, E. González-Guardia, M. Maldonado, R. Marino, I. Martínez-Delgado, I. Morales Durán, E. Mújica, S. Pascual, A. Pérez-Calpena, A. Sánchez-Penim, E. Sánchez-Blanco, F. Serena, S. Tulloch, V. Villar, J. Zamorano , D. Barrado y Naváscues, E. Bertone, N. Cardiel, A. Cava, J. Cenarro, M. Chávez, M. García, J. Guichard, R. Gúzman, A. Herrero, N. Huélamo, D. Hughes, J. Iglesias, J. Jiménez-Vicente, A. Aguerri, D. Mayya, J. Abreu, M. Mollá, C. Muñoz-Tuñón, S. Peimbert, M. Peimbert, P. Pérez-González, E. Pérez Montero, M. Rodríguez, J. M. Rodríguez-Espinosa, L. Rodríguez-Merino, D. Rosa, J. Sánchez-Almeida, C. Sánchez Contreras, Patricia Sánchez-Blázquez, S. Sánchez, A. Sarajedini, S. Silich, S. Simón, G. Tenorio-Tagle, E. Terlevich, R. Terlevich, I. Trujillo, Y. Tsamis, O. Vega
In these proceedings we give a summary of the characteristics and current status of the MEGARA instrument,
the future optical IFU and MOS for the 10.4-m Gran Telescopio Canarias (GTC). MEGARA is being built
by a Consortium of public research institutions led by the Universidad Complutense de Madrid (UCM, Spain)
that also includes INAOE (Mexico), IAA-CSIC (Spain) and UPM (Spain). The MEGARA IFU includes two
different fiber bundles, one called LCB (Large Compact Bundle) with a field-of-view of 12.5×11.3 arcsec2 and
a spaxel size of 0.62 arcsec yielding spectral resolutions between R=6,800-17,000 and another one called SCB
(Small Compact Bundle) covering 8.5×6.7 arcsec2 with hexagonally-shaped and packed 0.42-arcsec spaxels and
resolutions R=8,000-20,000. The MOS component allows observing up to 100 targets in 3.5×3.5 arcmin2. Both
the IFU bundles and the set of 100 robotic positioners of the MOS will be placed at one of the GTC Folded-Cass
foci while the spectrographs (one in the case of the MEGARA-Basic concept) will be placed at the Nasmyth
platform. On March 2012 MEGARA passed the Preliminary Design Review and its first light is expected to
take place at the end of 2015.
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