Examinando por Autor "Rodrigo, C."

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Restringido
A Catalog of Wide Binary and Multiple Systems of Bright Stars from Gaia-DR2 and the Virtual Observatory
(The Institute of Physics (IOP), 2019-01-28) Jiménez Esteban, F. M.; Rodrigo, C.; Solano, Enrique; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); European Research Council (ERC); Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Binary and multiple stars have long provided an effective empirical method of testing stellar formation and evolution theories. In particular, the existence of wide binary systems (separations >20,000 au) is particularly challenging to binary formation models as their physical separations are beyond the typical size of a collapsing cloud core (~5000–10,000 au). We mined the recently published Gaia-DR2 catalog to identify bright comoving systems in the five-dimensional space (sky position, parallax, and proper motion). We identified 3741 comoving binary and multiple stellar candidate systems, out of which 575 have compatible radial velocities for all the members of the system. The candidate systems have separations between ~400 and 500,000 au. We used the analysis tools of the Virtual Observatory to characterize the comoving system members and to assess their reliability. The comparison with previous comoving systems catalogs obtained from TGAS showed that these catalogs contain a large number of false systems. In addition, we were not able to confirm the ultra-wide binary population presented in these catalogs. The robustness of our methodology is demonstrated by the identification of well known comoving star clusters and by the low contamination rate for comoving binary systems with projected physical separations <50,000 au. These last constitute a reliable sample for further studies. The catalog is available online at the Spanish Virtual Observatory portal (http://svo2.cab.inta-csic.es/vocats/v2/comovingGaiaDR2/).
Acceso Abierto
A Catalog of Wide Binary and Multiple Systems of Bright Stars from Gaia-DR2 and the Virtual Observatory
(American Astronomical Society, 2019) Jiménez Esteban, F. M.; Rodrigo, C.; Solano, Enrique
Binary and multiple stars have long provided an effective empirical method of testing stellar formation and evolution theories. In particular, the existence of wide binary systems (separations >20,000 au) is particularly challenging to binary formation models as their physical separations are beyond the typical size of a collapsing cloud core (∼5000-10,000 au). We mined the recently published Gaia-DR2 catalog to identify bright comoving systems in the five-dimensional space (sky position, parallax, and proper motion). We identified 3741 comoving binary and multiple stellar candidate systems, out of which 575 have compatible radial velocities for all the members of the system. The candidate systems have separations between ∼400 and 500,000 au. We used the analysis tools of the Virtual Observatory to characterize the comoving system members and to assess their reliability. The comparison with previous comoving systems catalogs obtained from TGAS showed that these catalogs contain a large number of false systems. In addition, we were not able to confirm the ultra-wide binary population presented in these catalogs. The robustness of our methodology is demonstrated by the identification of well known comoving star clusters and by the low contamination rate for comoving binary systems with projected physical separations <50,000 au. These last constitute a reliable sample for further studies. The catalog is available online at the Spanish Virtual Observatory portal (http://svo2.cab.inta-csic.es/vocats/v2/comovingGaiaDR2/).
Acceso Abierto
Homogeneous study of Herbig Ae/Be stars from spectral energy distributions and Gaia EDR3
(EDP Sciences, 2021-06-25) Guzmán Díaz, J.; Mendigutía, I.; Montesinos, B.; Oudmaijer, R. D.; Vioque, M.; Rodrigo, C.; Meeus, G.; Marcos Arenal, P.; Solano, Enrique; Comunidad de Madrid; Agencia Estatal de Investigación (AEI); European Research Council (ERC)
Context. Herbig Ae/Be stars (HAeBes) have so far been studied based on relatively small samples that are scattered throughout the sky. Their fundamental stellar and circumstellar parameters and statistical properties were derived with heterogeneous approaches before Gaia. Aims. Our main goal is to contribute to the study of HAeBes from the largest sample of such sources to date, for which stellar and circumstellar properties have been determined homogeneously from the analysis of the spectral energy distributions (SEDs) and Gaia EDR3 parallaxes and photometry. Methods. Multiwavelength photometry was compiled for 209 bona fide HAeBes for which Gaia EDR3 distances were estimated. Using the Virtual Observatory SED Analyser (VOSA), photospheric models were fit to the optical SEDs to derive stellar parameters, and the excesses at infrared (IR) and longer wavelengths were characterized to derive several circumstellar properties. A statistical analysis was carried out to show the potential use of such a large dataset. Results. The stellar temperature, luminosity, radius, mass, and age were derived for each star based on optical photometry. In addition, their IR SEDs were classified according to two different schemes, and their mass accretion rates, disk masses, and the sizes of the inner dust holes were also estimated uniformly. The initial mass function fits the stellar mass distribution of the sample within 2 < M*∕M⊙ < 12. In this aspect, the sample is therefore representative of the HAeBe regime and can be used for statistical purposes when it is taken into account that the boundaries are not well probed. Our statistical study does not reveal any connection between the SED shape from the Meeus et al. (2001, A&A, 365, 476) classification and the presence of transitional disks, which are identified here based on the SEDs that show an IR excess starting at the K band or longer wavelengths. In contrast, only ~28% of the HAeBes have transitional disks, and the related dust disk holes are more frequent in HBes than in HAes (~34% vs. 15%). The relatively small inner disk holes and old stellar ages estimated for most transitional HAes indicate that photoevaporation cannot be the main mechanism driving disk dissipation in these sources. In contrast, the inner disk holes and ages of most transitional HBes are consistent with the photoevaporation scenario, although these results alone do not unambiguously discard other disk dissipation mechanisms.Conclusions. The complete dataset is available online through a Virtual Observatory-compliant archive, representing the most recent reference for statistical studies on the HAeBe regime. VOSA is a complementary tool for the future characterization of newly identified HAeBes.
Restringido
Identification of asteroids using the Virtual Observatory: the WFCAM Transit Survey
(Oxford Academics: Oxford University Press, 2019-10-26) Cortés Contreras, M.; Jiménez Esteban, F. M.; Mahlke, M.; Durech, J.; Barceló Forteza, S.; Rodrigo, C.; Velasco, A.; Carry, B.; Solano, Enrique; Agencia Estatal de Investigación (AEI); European Space Agency (ESA); Contreras, M. [0000-0003-3734-9866]; Rodrigo Blanco, C. [0000-0001-6068-0077]; Jiménez Esteban, F. M. [0000-0002-6985-9476]; Carry, B. [0000-0001-5242-3089]; Solano, E. [0000-0003-1885-5130]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The nature and physical properties of asteroids, in particular those orbiting in the near-Earth space, are of scientific interest and practical importance. Exoplanet surveys can be excellent resources to detect asteroids, both already known and new objects. This is due to their similar observing requirements: large fields of view, long sequences, and short cadence. If the targeted fields are not located far from the ecliptic, many asteroids will cross the field of view occasionally. We present two complementary methodologies to identify asteroids serendipitously observed in large-area astronomical surveys. One methodology focuses on detecting already known asteroids using the Virtual Observatory tool SkyBoT, which predicts their positions and motions in the sky at a specific epoch. The other methodology applies the ssos pipeline, which is able to identify known and new asteroids based on their apparent motion. The application of these methods to the 6.4 deg2 of the sky covered by the Wide-Field CAMera Transit Survey in the J-band is described. We identified 15 661 positions of 1821 different asteroids. Of them, 182 are potential new discoveries. A publicly accessible online, Virtual Observatory compliant catalogue was created. We obtained the shapes and periods for five of our asteroids from their light curves built with additional photometry taken from external archives. We demonstrated that our methodologies are robust and reliable approaches to find, at zero cost of observing time, asteroids observed by chance in astronomical surveys. Our future goal is to apply them to other surveys with adequate temporal coverage.
Restringido
Infrared-excess white dwarfs in the Gaia 100 pc sample
(Oxford Academics: Oxford University Press, 2019-09-02) Rebassa Mansergas, A.; Xu, S.; Rodrigo, C.; Jiménez Esteban, F. M.; Torres, S.; Solano, Enrique; Agencia Estatal de Investigación (AEI); Rodrigo, C. [0000-0001-6068-0077]; Xu, S. [0000-0002-8808-4282]; Jiménez Esteban, F. M. [0000-0002-6985-9476]; Solano, E. [0000-0003-1885-5130]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We analyse the 100 pc Gaia white dwarf volume-limited sample by means of VOSA (Virtual Observatory SED Analyser) with the aim of identifying candidates for displaying infrared excesses. Our search focuses on the study of the spectral energy distribution (SED) of 3733 white dwarfs with reliable infrared photometry and GBP − GRP colours below 0.8 mag, a sample that seems to be nearly representative of the overall white dwarf population. Our search results in 77 selected candidates, 52 of which are new identifications. For each target, we apply a two-component SED fitting implemented in VOSA to derive the effective temperatures of both the white dwarf and the object causing the excess. We calculate a fraction of infrared-excess white dwarfs due to the presence of a circumstellar disc of 1.6 ± 0.2 per cent, a value that increases to 2.6 ± 0.3 per cent if we take into account incompleteness issues. Our results are in agreement with the drop in the percentage of infrared excess detections for cool (<8000 K) and hot (>20 000 K) white dwarfs obtained in previous analyses. The fraction of white dwarfs with brown dwarf companions we derive is ≃0.1–0.2 per cent.
Acceso Abierto
J-PLUS: Discovery and characterisation of ultracool dwarfs using Virtual Observatory tools
(EDP Sciences, 2019-06-27) Martín, E. L.; Caballero, J. A.; Rodrigo, C.; Angulo, R. E.; Alcaniz, J. S.; Borges Fernandes, M.; Cenarro, A. J.; Cristóbal Hornillos, D.; Dupke, R. A.; Alfaro, E. J.; Ederoclite, A.; Jiménez Esteban, F. M.; Hernández Jiménez, J. A.; Hernández Monteagudo, C.; Lopes de Oliveira, R.; López Sanjuan, C.; Marín Franch, A.; Mendes de Oliveira, Claudia L.; Moles, M.; Orsi, Álvaro A.; Schmidtobreick, L.; Sobral, D.; Sodré, L.; Varela, J.; Vázquez Ramió, H.; Solano, Enrique; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Comisión Nacional de Investigación Científica y Tecnológica (CONICYT); European Research Council (ERC); Caballero, J. A. [https://orcid.org/0000-0002-7349-1387]; Jailson Souza de Alcaniz. [https://orcid.org/0000-0003-2441-1413]; Alfaro, Emilio J. [https://orcid.org/0000-0002-2234-7035]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. Ultracool dwarfs are objects with spectral types equal to or later than M7. Most of them have been discovered using wide-field imaging surveys. The Virtual Observatory has proven to be very useful for efficiently exploiting these astronomical resources. Aims. We aim to validate a Virtual Observatory methodology designed to discover and characterise ultracool dwarfs in the J-PLUS photometric survey. J-PLUS is a multiband survey carried out with the wide-angle T80Cam optical camera mounted on the 0.83 m telescope JAST/T80 in the Observatorio Astrofísico de Javalambre. We make use of the Internal Data Release covering 528 deg2. Methods. We complemented J-PLUS photometry with other catalogues in the optical and infrared using VOSA, a Virtual Observatory tool that estimates physical parameters from the spectral energy distribution fitting to collections of theoretical models. Objects identified as ultracool dwarfs were distinguished from background M giants and highly reddened stars using parallaxes and proper motions from Gaia DR2. Results. We identify 559 ultracool dwarfs, ranging from i = 16.2 mag to i = 22.4 mag, of which 187 are candidate ultracool dwarfs not previously reported in the literature. This represents an increase in the number of known ultracool dwarfs of about 50% in the region of the sky we studied, particularly at the faint end of our sensitivity, which is interesting as reference for future wide and deep surveys such as Euclid. Three candidates are interesting targets for exoplanet surveys because of their proximity (distances less than 40 pc). We also analysed the kinematics of ultracool dwarfs in our catalogue and found evidence that it is consistent with a Galactic thin-disc population, except for six objects that might be members of the thick disc. Conclusion. The results we obtained validate the proposed methodology, which will be used in future J-PLUS and J-PAS releases. Considering the region of the sky covered by the Internal Data Release used in this work, we estimate that 3000–3500 new ultracool dwarfs will be discovered at the end of the J-PLUS project.
Restringido
The Gran Telescopio Canarias OSIRIS broad-band first data release
(Oxford Academics: Oxford University Press, 2020-01-05) Cortés Contreras, M.; Bouy, H.; Mahlke, M.; Jiménez Esteban, F. M.; Alacid, J. M.; Rodrigo, C.; Solano, Enrique; European Space Agency (ESA); Agencia Estatal de Investigación (AEI); European Research Council (ERC); Cortés Contreras, M. [0000-0003-3734-9866]; Rodrigo, C. [0000-0001-6068-0077]; Solano, E. [0000-0003-1885-5130]; Jiménez Esteban, F. M. [0000-0002-6985-9476]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We present the first release of GTC OSIRIS broad-band data archive. This is an effort conducted in the framework of the Spanish Virtual Observatory to help optimize science from the Gran Telescopio Canarias Archive. Data Release 1 includes 6788 broad-band images in the Sloan griz filters obtained between 2009 April and 2014 January and the associated catalogue with roughly 6.23 million detections of more than 630 000 unique sources. The catalogue contains standard PSF and Kron aperture photometry with a mean accuracy better than 0.09 and 0.15 mag, respectively. The relative astrometric residuals are always better than 30 mas and better than 15 mas in most cases. The absolute astrometric uncertainty of the catalogue is of 0.12 arcsec. In this paper we describe the procedure followed to build the image archive and the associated catalogue, as well as the quality tests carried out for validation. To illustrate some of the scientific potential of the catalogue, we also provide two examples of its scientific exploitation: discovery and identification of asteroids and cool dwarfs.
Restringido
Ultracool dwarfs in deep extragalactic surveys using the virtual observatory: ALHAMBRA and COSMOS
(Oxford Academics: Oxford University Press, 2021-02-01) Gálvez Ortiz, M. C.; Martín, E. L.; Gómez Muñoz, I. M.; Rodrigo, C.; Burgasser, A. J.; Lodieu, N.; Béjar, V. J. S.; Huélamo, N.; Morales Calderón, M.; Bouy, H.; Solano, Enrique; Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Ultracool dwarfs (UCDs) encompass a wide variety of compact stellar-like objects with spectra classified as late-M, L, T, and Y. Most of them have been discovered using wide-field imaging surveys. The Virtual Observatory (VO) has proven to be of great utility to efficiently exploit these astronomical resources. We aim to validate a VO methodology designed to discover and characterize UCDs in deep extragalactic surveys like Advance Large Homogeneous Area Medium-Band Redshift Astronomical (ALHAMBRA) and Cosmological Evolution Survey (COSMOS). Three complimentary searches based on parallaxes, proper motions and colours, respectively, were carried out. A total of 897 candidate UCDs were found, with only 16 previously reported in SIMBAD. Most of the new UCDs reported here are likely late-M and L dwarfs because of the limitations imposed by the utilization of optical (Gaia DR2 and r-band) data. We complement ALHAMBRA and COSMOS photometry with other catalogues in the optical and infrared using VOSA, a VO tool that estimates effective temperatures from the spectral energy distribution fitting to collections of theoretical models. The agreement between the number of UCDs found in the COSMOS field and theoretical estimations together with the low false-negative rate (known UCDs not discovered in our search) validates the methodology proposed in this work, which will be used in the forthcoming wide and deep surveys provided by the Euclid space mission. Simulations of Euclid number counts for UCDs detectable in different photometric passbands are presented for a wide survey area of 15 000 deg2, and the limitations of applicability of Euclid data to detect UCDs using the methods employed in this paper are discussed.