Examinando por Autor "Daflon, S."

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Acceso Abierto
Deriving stellar parameters from GALANTE photometry: bias and precision
(Oxford Academics: Oxford University Press, 2020-04-09) Lorenzo Gutiérrez, A.; Alfaro, E. J.; Maíz Apellániz, J.; Barbá, R. H.; Marín Franch, A.; Ederoclite, A.; Cristóbal Hornillos, D.; Varela, J.; Vázquez Ramió, H.; Cenarro, A. J.; Lennon, D. J.; García Lario, P.; Daflon, S.; Borges Fernandes, M.; Agencia Estatal de Investigación (AEI); Maíz Apellániz, J. [0000-0003-0825-3443]; Marín Franch, A. [0000-0002-9026-3933]; Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
In this paper, we analyse how to extract the physical properties from the GALANTE photometry of a stellar sample. We propose a direct comparison between the observational colours (photometric bands normalized to the 515 nm central wavelength) and the synthetic colours derived from different stellar libraries. We use the reduced χ2 as the figure of merit for selecting the best fitting between both colour sets. The synthetic colours of the Next Generation Spectral Library (NGSL) provide a valuable sample for testing the uncertainty and precision of the stellar parameters derived from observational data. Reddening, as an extrinsic stellar physical parameter becomes a crucial variable for accounting for the errors and bias in the derived estimates: the higher the reddenings, the larger the errors and uncertainties in the derived parameters. NGSL colours also enable us to compare different theoretical stellar libraries for the same set of physical parameters, where we see how different catalogues of models can provide very different solutions in a, sometimes, non-linear way. This peculiar behaviour makes us to be cautious with the derived physical parameters obtained from GALANTE photometry without previous detailed knowledge of the theoretical libraries used to this end. In addition, we carry out the experiment of deriving physical stellar parameters from some theoretical libraries, using some other libraries as observational data. In particular, we use the Kurucz and Coelho libraries, as input observational data, to derive stellar parameters from Coelho + TLUSTY and Kurucz + TLUSTY stellar libraries, respectively, for different photometric errors and colour excesses.© 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society
Acceso Abierto
J-PLUS: The Javalambre Photometric Local Universe Survey
(EDP Sciences, 2019-02-21) Cenarro, A. J.; Moles, M.; Cristóbal Hornillos, D.; Marín Franch, A.; Ederoclite, A.; Varela, J.; López Sanjuan, C.; Hernández Monteagudo, C.; Angulo, R. E.; Vázquez Ramió, H.; Viironen, K.; Reis, R. R. R.; Molino, A.; Roig, F.; Vilella-Rojo, G.; Sako, M.; Sánchez Blázquez, P.; Gurung López, S.; Santos, W. A.; Telles, E.; Allende Prieto, C.; Bonatto, C.; Vilchez, J. M.; San Roman, I.; Daflon, S.; Dupke, R. A.; Greisel, N.; Jiménez Teja, Y.; Placco, V. M.; Logroño García, R.; Spinoso, D.; Maícas, N.; Izquierdo Villalba, D.; Abril, J.; Aguerri, J. A. L.; Carvano, J. M.; Bielsa de Toledo, S.; Chies Santos, A. L.; Falcón Barroso, J.; Civera, T.; Gonçalves, D. R.; Hernández Fuertes, J.; Iglesias Marzoa, R.; Whitten, D. D.; Antón, J. L.; Kruuse, K.; Lamadrid, J. L.; Bello, R.; Castillo Ramírez, J.; López Sainz, A.; Moreno Signes, A.; Chueca, S.; Díaz Martín, M. C.; Beers, T. C.; Domínguez Martínez, M.; Rueda Teruel, F.; Garzarán Calderaro, J.; Iñiguez, C.; Tilve, V.; Jiménez Ruiz, J. M.; Lasso Cabrera, N.; Alcaniz, J. S.; López Alegre, G.; Muniesa, D. J.; Lopes de Oliveira, R.; Tamm, A.; Rodríguez Llano, S.; Rueda Teruel, S.; Akras, S.; Alfaro, E. J.; Soriano Laguía, I.; Valdivielso, L.; Beasley, M. A.; Borges Fernandes, M.; Yanes Díaz, A.; Mendes de Oliveira, Claudia L.; Lyman, J. D.; Sodré, L.; Carrasco, J. M.; Coelho, P. R. T.; Xavier, H. S.; Costa Duarte, M. V.; Abramo, L. R.; Álvarez Candal, A.; Galarza, A.; Ascaso, B.; Bruzual, G.; González Serrano, J. I.; Gutiérrez Soto, L. A.; Buzzo, M. L.; Cepa, J.; Kuncarayakti, H.; Landim, R. C. G.; Cortesi, A.; De Prá, M.; Lima Neto, G. B.; Maíz Apellániz, J.; Favole, G.; Galbany, L.; Orsi, Álvaro A.; García, K.; Nogueira Cavalcante, J. P.; González Delgado, R. M.; Hernández Jiménez, J. A.; Oteo, I.; Kanaan, A.; Laur, J.; Rebassa-Mansergas, A.; Lincandro, J.; Miralda Escudé, J.; Salvador Rusiñol, N.; Sampedro, L.; Morate, D.; Novais, P. M.; Schmidtobreick, L.; Siffert, B. B.; Oncins, M.; Overzier, R. A.; Bonoli, S.; Hurier, G.; Pereira, C. B.; Díaz García, Pedro; Solano, Enrique; Gobierno de Aragón; European Commission (EC); Conselho Nacional de Desenvolvimento Científico e Tecnológico; Financiadora de Estudos e Projetos (FINEP); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); National Science Foundation (NSF); Ministerio de Economía y Competitividad (MINECO); 0000-0002-2573-2342; Jailson Souza de Alcaniz. [https://orcid.org/0000-0003-2441-1413]; Coelho, P. R. T. [0000-0003-1846-4826]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The Javalambre Photometric Local Universe Survey (J-PLUS ) is an ongoing 12-band photometric optical survey, observing thousands of square degrees of the Northern Hemisphere from the dedicated JAST/T80 telescope at the Observatorio Astrofísico de Javalambre (OAJ). The T80Cam is a camera with a field of view of 2 deg2 mounted on a telescope with a diameter of 83 cm, and is equipped with a unique system of filters spanning the entire optical range (3500–10 000 Å). This filter system is a combination of broad-, medium-, and narrow-band filters, optimally designed to extract the rest-frame spectral features (the 3700–4000 Å Balmer break region, Hδ, Ca H+K, the G band, and the Mg b and Ca triplets) that are key to characterizing stellar types and delivering a low-resolution photospectrum for each pixel of the observed sky. With a typical depth of AB ∼21.25 mag per band, this filter set thus allows for an unbiased and accurate characterization of the stellar population in our Galaxy, it provides an unprecedented 2D photospectral information for all resolved galaxies in the local Universe, as well as accurate photo-z estimates (at the δ z/(1 + z)∼0.005–0.03 precision level) for moderately bright (up to r ∼ 20 mag) extragalactic sources. While some narrow-band filters are designed for the study of particular emission features ([O II]/λ3727, Hα/λ6563) up to z < 0.017, they also provide well-defined windows for the analysis of other emission lines at higher redshifts. As a result, J-PLUS has the potential to contribute to a wide range of fields in Astrophysics, both in the nearby Universe (Milky Way structure, globular clusters, 2D IFU-like studies, stellar populations of nearby and moderate-redshift galaxies, clusters of galaxies) and at high redshifts (emission-line galaxies at z ≈ 0.77, 2.2, and 4.4, quasi-stellar objects, etc.). With this paper, we release the first ∼1000 deg2 of J-PLUS data, containing about 4.3 million stars and 3.0 million galaxies at r < 21 mag. With a goal of 8500 deg2 for the total J-PLUS footprint, these numbers are expected to rise to about 35 million stars and 24 million galaxies by the end of the survey.
Acceso Abierto
J-PLUS: Tools to identify compact planetary nebulae in the Javalambre and southern photometric local Universe surveys
(EDP Sciences, 2020-01-21) Gutiérrez Soto, L. A.; Gonçalves, D. R.; Akras, S.; Cortesi, A.; López Sanjuan, C.; Guerrero, Martín A.; Daflon, S.; Borges Fernandes, M.; Mendes de Oliveira, Claudia L.; Ederoclite, A.; Sodré, L.; Pereira, C. B.; Kanaan, A.; Werle, A.; Vázquez Ramió, H.; Alcaniz, J. S.; Angulo, R. E.; Cenarro, A. J.; Cristóbal Hornillos, D.; Dupke, R. A.; Hernández Monteagudo, C.; Marín Franch, A.; Moles, M.; Varela, J.; Ribeiro, T.; Schoenell, W.; Álvarez Candal, A.; Galbany, L.; Jiménez Esteban, F. M.; Logroño García, R.; Sobral, D.; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); European Research Council (ERC); Ministerio de Economía y Competitividad (MINECO); Guitiérrez Soto, L. A. [0000-0002-9891-8017]
Context. From the approximately 3500 planetary nebulae (PNe) discovered in our Galaxy, only 14 are known to be members of the Galactic halo. Nevertheless, a systematic search for halo PNe has never been performed. Aims. In this study, we present new photometric diagnostic tools to identify compact PNe in the Galactic halo by making use of the novel 12-filter system projects, Javalambre Photometric Local Universe Survey (J-PLUS) and Southern-Photometric Local Universe Survey (S-PLUS). Methods. We reconstructed the Isaac Newton Telescope Photometric H alpha Survey of the Northern Galactic Plane diagnostic diagram and propose four new ones using (i) the J-PLUS and S-PLUS synthetic photometry for a grid of photo-ionisation models of halo PNe, (ii) several observed halo PNe, as well as (iii) a number of other emission-line objects that resemble PNe. All colour-colour diagnostic diagrams are validated using two known halo PNe observed by J-PLUS during the scientific verification phase and the first data release (DR1) of S-PLUS and the DR1 of J-PLUS. Results. By applying our criteria to the DR1s (similar to 1190 deg(2)), we identified one PN candidate. However, optical follow-up spectroscopy proved it to be a HII region belonging to the UGC 5272 galaxy. Here, we also discuss the PN and two HII galaxies recovered by these selection criteria. Finally, the cross-matching with the most updated PNe catalogue (HASH) helped us to highlight the potential of these surveys, since we recover all the known PNe in the observed area. Conclusions. The tools here proposed to identify PNe and separate them from their emission-line contaminants proved to be very efficient thanks to the combination of many colours, even when applied - like in the present work - to an automatic photometric search that is limited to compact PNe.