67 research outputs found

    EMIR at the GTC: results on the first commissioning at the telescope

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    We report the results on the EMIR1 (Espectrografo Multiobjeto Infra-Rojo) performances after the commissioning period of the instrument at the Gran Telescopio Canarias (GTC). EMIR is one of the first common user instruments for the GTC, the 10 meter telescope operating at the Roque de los Muchachos Observatory (La Palma, Canary Islands, Spain). EMIR is being built by a Consortium of Spanish and French institutes led by the Instituto de Astrofisica de Canarias (IAC). EMIR is primarily designed to be operated as a MOS in the K band, but offers a wide range of observing modes, including imaging and spectroscopy, both long slit and multiobject, in the wavelength range 0.9 to 2.5 mu m. The development and fabrication of EMIR is funded by GRANTECAN and the Plan Nacional de Astronomia y Astrofisica (National Plan for Astronomy and Astrophysics, Spain). After an extensive and intensive period of system verification at the IAC, EMIR was shipped to the GTC on May 2016 for its integration at the Nasmyth platform. Once in the observatory, several tests were conducted to ensure the functionality of EMIR at the telescope, in particular that of the ECS (EMIR Control System) which has to be fully embedded into the GCS (GTC Control System) so as to become an integral part of it. During the commissioning, the main capabilities of EMIR and its combined operation with the GTC are tested and the ECS are modified to its final form. This contribution reports on the details of the EMIR operation at the GTC obtained so far, on the first commissioning period

    The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase.

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    © The Author(s) 2023. Artículo firmado por 304 autores. This paper is based on the documentation assembled by the CNES project team and the Consortium partners for the X-IFU System Requirement Review, which has started at the end of June, albeit with reduced objectives (the review will be completed in September 2022). DB wishes to thank the CNES Project and Support teams for continuing the preparation of the SRR data pack, during the disruptive and unfortunate events that happened to Athena, which could have led to the termination of X-IFU. There is no doubt that their efforts will be rewarded in the upcoming design-to-cost exercise. DB would also like to express his gratitude to the CNES Management (Philippe Baptiste, President), Lionel Suchet (Chief Operating Officer), Caroline Laurent (Director of orbital systems and applications), Philippe Lier (Deputy-Director of orbital systems and applications), the French ESA SPC delegation (Olivier La Marle and Juliette Lambin) for their unfailing support to X-IFU. This support was instrumental in preserving an X-IFU on the new Athena mission and will remain precious in the upcoming phase of the reformulation of the mission. Special thanks to all the SPC delegations which supported the objective of keeping a flagship X-ray observatory in the ESA Science Program. DB is also thankful to Gilles Bergametti (President of the CNES Comit´e des Programmes Scientifiques, CPS), Athena Coustenis (President of the CNES Comit´e d’´evaluation de la recherche et de l’exploration spatiale, CERES) and Pierre-Olivier Petrucci (President of the Programme National des Hautes Energies) for their support and for providing the feedback from the French scientific community at large. The French contribution to X-IFU is funded by CNES, CNRS and CEA. This work has been also supported by ASI (Italian Space Agency) through the Contract 2019-27-HH.0, and by the ESA (European Space Agency) Core Technology Program (CTP) Contract No. 4000114932/15/NL/BW and the AREMBES - ESA CTP No.4000116655/16/NL/BW. This publication is part of grant RTI2018-096686-B-C21 funded by MCIN/AEI/ 10.13039/501100011033 and by “ERDF A way of making Europe”. This publication is part of grant RTI2018-096686-B-C21 and PID2020-115325GB-C31 funded by MCIN/AEI/10.13039/501100011033.The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory. Athena is a versatile observatory designed to address the Hot and Energetic Universe science theme, as selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), X-IFU aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over an hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR (i.e. in the course of its preliminary definition phase, so-called B1), browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters, such as the instrument efficiency, spectral resolution, energy scale knowledge, count rate capability, non X-ray background and target of opportunity efficiency. Finally, we briefly discuss the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, touch on communication and outreach activities, the consortium organisation and the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. The X-IFU will be provided by an international consortium led by France, The Netherlands and Italy, with ESA member state contributions from Belgium, Czech Republic, Finland, Germany, Poland, Spain, Switzerland, with additional contributions from the United States and Japan.Depto. de Física de la Tierra y AstrofísicaFac. de Ciencias FísicasTRUECNES Project and SupportCNRSCEAASI (Italian Space Agency)ESA (European Space Agency) Core Technology Program (CTP)AREMBES - ESA CTPMinisterio de Ciencia e InnovaciónERDF "A way of making Europe"pu

    FRIDA: diffraction -limited imaging and integral-field spectroscopy for the GTC

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    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

    MIRADAS for the Gran Telescopio Canarias

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    The Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS, a near-infrared multi-object echelle spectrograph operating at spectral resolution R=20,000 over the 1-2.5 mu m bandpass) was selected by the Gran Telescopio Canarias (GTC) partnership as the next-generation near-infrared spectrograph for the world's largest optical/infrared telescope, and is being developed by an international consortium. The MIRADAS consortium includes the University of Florida, Universidad de Barcelona, Universidad Complutense de Madrid, Instituto de Astrofisica de Canarias, and Institut d'Estudis Espacials de Catalunya, as well as probe arm industrial partner A-V-S (Spain), with more than 45 Science Working Group members in 10 institutions primarily in Spain, Mexico, and the USA. In this paper, we review the overall system design and project status for MIRADAS during its early fabrication phase in 2016

    FRIDA: diffraction -limited imaging and integral-field spectroscopy for the GTC

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    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

    Spectral gradients in central cluster galaxies: further evidence of star formation in cooling flows

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    We have obtained radial gradients in the spectral features of the lambda 4000-Angstrom break (D(4000)) and Mg(2) for a sample of 11 central cluster galaxies (CCGs): eight in clusters with cooling flows and three in clusters without. After careful removal of the emission lines found within the D(4000) and Mg(2) bandpasses for some objects, the new data strongly confirm the correlations between line-strength indices and the cooling flow phenomenon found in our earlier study. We find that such correlations depend on the presence and characteristics of emission lines in the inner regions of the CCGs. The nuclear indices are correlated with the mass deposition rate ((M) over dot) only when emission lines are found in the central regions of the galaxies. The central D(4000) and Mg(2) indices in cooling flow galaxies without emission lines are completely consistent with the indices measured in CCGs in clusters without cooling flows. CCGs in cooling flow clusters exhibit a clear sequence in the D(4000)-Mg(2) plane, with a neat segregation depending on emission-line type and blue morphology. This sequence can be modelled, using stellar population models with a normal initial mass function (IMF), by a recent (similar to 0.1 Gyr old) burst of star formation, although model uncertainties do not allow us to completely discard continuous star formation or a series of bursts over the last few Gyr. In CCGs with emission lines, the gradients in the spectral indices are flat or positive inside the emission-line regions, suggesting the presence of young stars. Outside the emission-line regions, and in cooling flow galaxies without emission lines, gradients are negative and consistent with those measured in CCGs in clusters without cooling hows and giant elliptical galaxies. Index gradients measured exclusively in the emission-line region correlate with hi. Using the same population models we have estimated the radial profiles of the mass transformed into new stars. The derived profiles are remarkably parallel to the expected radial behaviour of the mass deposition rate derived from X-ray observations. Moreover, a large fraction (probably most) of the cooling flow gas accreted into the emission-line region is converted into stars. In the Light of these new data, we discuss the evolutionary sequence suggested by McNamara, in which radio-triggered star formation bursts take place several times during the lifetime of the cooling flow. We conclude that this scenario is consistent with the available observations

    Higher prevalence of X-ray selected AGN in intermediate-age galaxies up to z similar to 1

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    We analyse the stellar populations in the host galaxies of 53 X-ray selected optically dull active galactic nuclei (AGN) at 0.34 10(10.5) M circle dot) and that the observed fraction of galaxies hosting an AGN increases with the stellar mass. A careful selection of random control samples of inactive galaxies allows us to remove the stellar mass and redshift dependences of the AGN fraction to explore trends with several stellar age indicators. We find no significant differences in the distribution of the rest-frame U - V colour for AGN hosts and inactive galaxies, in agreement with previous results. However, we find significantly shallower 4000 angstrom bres in AGN hosts, indicative of younger stellar populations. With the help of a model-independent determination of the extinction, we obtain extinction-corrected U - V colours and light-weighted average stellar ages. We find that AGN hosts have younger stellar populations and higher extinction compared to inactive galaxies with the same stellar mass and at the same redshift. We find a highly significant excess of AGN hosts with D-n(4000) similar to 1.4 and light-weighted average stellar ages of 300-500 Myr, as well as a deficit of AGN in intrinsic red galaxies. We interpret failure in recognizing these trends in previous studies as a consequence of the balancing effect in observed colours of the age-extinction degeneracy

    FRIDA: diffraction-limited imaging and integral-field spectroscopy for the GTC

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    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

    NGC 7469 as seen by MEGARA: new results from high-resolution IFU spectroscopy

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    We present our analysis of high-resolution (R ∼ 20 000) GTC/MEGARA integral-field unit spectroscopic observations, obtained during the commissioning run, in the inner region (12.5 arcsec × 11.3 arcsec) of the active galaxy NGC 7469, at spatial scales of 0.62 arcsec. We explore the kinematics, dynamics, ionization mechanisms, and oxygen abundances of the ionized gas, by modelling the H α-[N II] emission lines at high signal-to-noise (> 15) with multiple Gaussian components. MEGARA observations reveal, for the first time for NGC 7469, the presence of a very thin (20 pc) ionized gas disc supported by rotation (V/σ = 4.3), embedded in a thicker (222 pc), dynamically hotter (V/σ = 1.3) one. These discs nearly corotate with similar peak-to-peak velocities (163 versus 137 km s^(−1)), but with different average velocity dispersion (38 ± 1 versus 108 ± 4 km s^(−1)). The kinematics of both discs could be possibly perturbed by star-forming regions. We interpret the morphology and the kinematics of a third (broader) component (σ > 250 km s^(−1)) as suggestive of the presence of non-rotational turbulent motions possibly associated either to an outflow or to the lense. For the narrow component, the [N II]/H α ratios point to the star-formation as the dominant mechanism of ionization, being consistent with ionization from shocks in the case of the intermediate component. All components have roughly solar metallicity. In the nuclear region of NGC 7469, at r ≤ 1.85 arcsec, a very broad (FWHM = 2590 km s^(−1)) H α component is contributing (41 per cent) to the global H α-[N II] profile, being originated in the (unresolved) broad line region of the Seyfert 1.5 nucleus of NGC 7469

    Evaluating human photoreceptoral inputs from night-time lights using RGB imaging photometry

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    Night-time lights interact with human physiology through different pathways starting at the retinal layers of the eye; from the signals provided by the rods; the S-, L- and M-cones; and the intrinsically photosensitive retinal ganglion cells (ipRGC). These individual photic channels combine in complex ways to modulate important physiological processes, among them the daily entrainment of the neural master oscillator that regulates circadian rhythms. Evaluating the relative excitation of each type of photoreceptor generally requires full knowledge of the spectral power distribution of the incoming light, information that is not easily available in many practical applications. One such instance is wide area sensing of public outdoor lighting; present-day radiometers onboard Earth-orbiting platforms with sufficient nighttime sensitivity are generally panchromatic and lack the required spectral discrimination capacity. In this paper, we show that RGB imagery acquired with off-the-shelf digital single-lens reflex cameras (DSLR) can be a useful tool to evaluate, with reasonable accuracy and high angular resolution, the photoreceptoral inputs associated with a wide range of lamp technologies. The method is based on linear regressions of these inputs against optimum combinations of the associated R, G, and B signals, built for a large set of artificial light sources by means of synthetic photometry. Given the widespread use of RGB imaging devices, this approach is expected to facilitate the monitoring of the physiological effects of light pollution, from ground and space alike, using standard imaging technology
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