Persona: Díaz García, Pedro
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Díaz García
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Publicación Acceso Abierto Stellar populations of galaxies in the ALHAMBRA survey up to z ∼ 1 IV. Properties of quiescent galaxies on the stellar mass–size plane(EDP Sciences, 2019-11-13) Cenarro, A. J.; López Sanjuan, C.; Peralta de Arriba, L.; Ferreras, I.; Cerviño, M.; Márquez, I.; Masegosa, J.; Del Olmo, A.; Perea, J.; Díaz García, Pedro; Gobierno de Aragón; Ministry of Science and Technology of Taiwan (MOST); Academia Sinica; Ministerio de Ciencia e Innovación (MICINN); Generalitat Valenciana; Junta de Andalucía; Generalitat de Catalunya; Ministerio de Economía y Competitividad (MINECO); Cerviño, M. [0000-0001-8009-231X]; De Arribas, L. P. [0000-0002-3084-084X]; López Sanjuan, C. [0000-0002-5743-3160]; Márquez Pérez, I. [0000-0003-2629-1945]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737Aims. We perform a comprehensive study of the stellar population properties (formation epoch, age, metallicity, and extinction) of quiescent galaxies as a function of size and stellar mass to constrain the physical mechanism governing the stellar mass assembly and the likely evolutive scenarios that explain their growth in size. Methods. After selecting all the quiescent galaxies from the ALHAMBRA survey by the dust-corrected stellar mass–colour diagram, we built a shared sample of ∼850 quiescent galaxies with reliable measurements of sizes from the HST. This sample is complete in stellar mass and luminosity, I ≤ 23. The stellar population properties were retrieved using the fitting code for spectral energy distributions called MUlti-Filter FITting for stellar population diagnostics (MUFFIT) with various sets of composite stellar population models. Age, formation epoch, metallicity, and extinction were studied on the stellar mass–size plane as function of size through a Monte Carlo approach. This accounted for uncertainties and degeneracy effects amongst stellar population properties. Results. The stellar population properties of quiescent galaxies and their stellar mass and size since z ∼ 1 are correlated. At fixed stellar mass, the more compact the quiescent galaxy, the older and richer in metals it is (1 Gyr and 0.1 dex, respectively). In addition, more compact galaxies may present slight lower extinctions than their more extended counterparts at the same stellar mass (< 0.1 mag). By means of studying constant regions of stellar population properties across the stellar mass–size plane, we obtained empirical relations to constrain the physical mechanism that governs the stellar mass assembly of the form M⋆ ∝ rcα, where α amounts to 0.50–0.55 ± 0.09. There are indications that support the idea that the velocity dispersion is tightly correlated with the stellar content of galaxies. The mechanisms driving the evolution of stellar populations can therefore be partly linked to the dynamical properties of galaxies, along with their gravitational potential.Publicación Acceso Abierto Novel design of superhydrophobic and anticorrosive PTFE and PAA + β − CD composite coating deposited by electrospinning, spin coating and electrospraying techniques(Multidisciplinary Digital Publishing Institute (MDPI), 2022-10-16) Vicente, Adrián; Rivero, Pedro J.; Urdiroz, U.; Mora, J.; Palacio, J. F.; Palomares, F. J.; Rodríguez, Rafael; Díaz García, Pedro; Asociación de la Industria Navarra (AIN); Agencia Estatal de Investigación (AEI)A superhydrophobic composite coating consisting of polytetrafluoroethylene (PTFE) and poly(acrylic acid)+ β-cyclodextrin (PAA + β-CD) was prepared on an aluminum alloy AA 6061T6 substrate by a three-step process of electrospinnig, spin coating, and electrospraying. The electrospinning technique is used for the fabrication of a polymeric binder layer synthesized from PAA + β-CD. The superhydrophilic characteristic of the electrospun PAA + β-CD layer makes it suitable for the absorption of an aqueous suspension with PTFE particles in a spin-coating process, obtaining a hydrophobic behavior. Then, the electrospraying of a modified PTFE dispersion forms a layer of distributed PTFE particles, in which a strong bonding of the particles with each other and with the PTFE particles fixed in the PAA + β-CD fiber matrix results in a remarkable improvement of the particles adhesion to the substrate by different heat treatments. The experimental results corroborate the important role of obtaining hierarchical micro/nano multilevel structures for the optimization of superhydrophobic surfaces, leading to water contact angles above 170°, very low contact angle of hysteresis (CAH = 2°) and roll-off angle (αroll−off < 5°). In addition, a superior corrosion resistance is obtained, generating a barrier to retain the electrolyte infiltration. This study may provide useful insights for a wide range of applicationsPublicación 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-2017-0737The 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.Publicación Acceso Abierto Calibration and performance of the NIKA2 camera at the IRAM 30-m Telescope.(EDP Sciences, 2020-05-18) Perotto, L.; Ponthieu, N.; Marcías Pérez, J. F.; Adam, R.; Ade, P.; André, P.; Andrianasolo, A.; Aussel, H.; Beelen, A.; Benoit, A.; Berta, S.; Bideaud, A.; Bourrion, O.; Calvo, M.; Catalano, A.; Comis, B.; De Petris, M.; Désert, F. X.; Doyle, S.; Driessen, E. F. C.; Gómez, A.; Goupy, J.; John, D.; Kéruzoré, F.; Kramer, C.; Ladjelate, B.; Lagache, G.; Leclercq, S.; Lestrade, L. F.; Maury, A.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Navarro, Sara; Peñalver, J.; Pierfederici, F.; Pisano, G.; Revéret, V.; Ritacco, A.; Roussel, H.; Ruppin, F.; Schuster, K.; Shu, S.; Sievers, A.; Tucker, C.; Zylka, R.; Díaz García, Pedro; Romero Guzman, Catalina; Agence Nationale de la Recherche (ANR); European Commission (EC); Ministerio de Economía y Competitividad (MINECO); Centre National D'Etudes Spatiales (CNES); 0000-0001-6937-5052; 0000-0002-3101-0768; 0000-0002-5385-2763; 0000-0001-6478-7883; 0000-0001-9995-4792; 0000-0002-8752-1401; 0000-0001-7859-2139; 0000-0002-6370-2101; 0000-0001-6397-5516; 0000-0002-1371-5705; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737Context. NIKA2 is a dual-band millimetre continuum camera of 2 900 kinetic inductance detectors, operating at 150 and 260 GHz, installed at the IRAM 30-m telescope in Spain. Open to the scientific community since October 2017, NIKA2 will provide key observations for the next decade to address a wide range of open questions in astrophysics and cosmology. Aims. Our aim is to present the calibration method and the performance assessment of NIKA2 after one year of observation. Methods. We used a large data set acquired between January 2017 and February 2018 including observations of primary and secondary calibrators and faint sources that span the whole range of observing elevations and atmospheric conditions encountered by the IRAM 30-m telescope. This allowed us to test the stability of the performance parameters against time evolution and observing conditions. We describe a standard calibration method, referred to as the "Baseline" method, to translate raw data into flux density measurements. This includes the determination of the detector positions in the sky, the selection of the detectors, the measurement of the beam pattern, the estimation of the atmospheric opacity, the calibration of absolute flux density scale, the flat fielding, and the photometry. We assessed the robustness of the performance results using the Baseline method against systematic effects by comparing results using alternative methods. Results. We report an instantaneous field of view of 6.5 ' in diameter, filled with an average fraction of 84%, and 90% of valid detectors at 150 and 260 GHz, respectively. The beam pattern is characterised by a FWHM of 17.6 '' +/- 0.1 '' and 11.1 '' +/- 0.2 '', and a main-beam efficiency of 47%+/- 3%, and 64%+/- 3% at 150 and 260 GHz, respectively. The point-source rms calibration uncertainties are about 3% at 150 GHz and 6% at 260 GHz. This demonstrates the accuracy of the methods that we deployed to correct for atmospheric attenuation. The absolute calibration uncertainties are of 5%, and the systematic calibration uncertainties evaluated at the IRAM 30-m reference Winter observing conditions are below 1% in both channels. The noise equivalent flux density at 150 and 260 GHz are of 9 +/- 1 mJy s(1/2) and 30 +/- 3 mJy s(1/2). This state-of-the-art performance confers NIKA2 with mapping speeds of 1388 +/- 174 and 111 +/- 11 arcmin(2) mJy(-2) h(-1) at 150 and 260 GHz. Conclusions. With these unique capabilities of fast dual-band mapping at high (better that 18 '') angular resolution, NIKA2 is providing an unprecedented view of the millimetre Universe.Publicación Acceso Abierto GASTON: Galactic Star Formation with NIKA2 – evidence for the mass growth of star-forming clumps(Oxford Academics: Oxford University Press, 2021-01-25) Rigby, A. J.; Peretto, N.; Adam, R.; Ade, P.; Anderson, M.; André, P.; Andrianasolo, A.; Aussel, H.; Bacmann, A.; Beelen, A.; Benoit, A.; Berta, S.; Bourrion, O.; Bracco, A.; Calvo, M.; Catalano, A.; De Petris, M.; Désert, F. X.; Doyle, S.; Driessen, E. F. C.; Gómez, A.; Goupy, J.; Kéruzoré, F.; Kramer, C.; Ladjelate, B.; Lagache, G.; Leclercq, S.; Lestrade, L. F.; Marcías Pérez, J. F.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Perotto, L.; Pisano, G.; Ponthieu, N.; Revéret, V.; Ristorcelli, I.; Ritacco, A.; Roussel, H.; Ruppin, F.; Schuster, K.; Shu, S.; Sievers, A.; Tucker, C.; Watkins, E. J.; Díaz García, Pedro; Romero Guzman, Catalina; Science and Technology Facilities Council (STFC); National Aeronautics and Space Administration (NASA); European Research Council (ERC); European Commission (EC); Ritacco, A. [0000-0003-0162-8206]; Rigby, A. J. [0000-0002-3351-2200]; Peretto, N. [0000-0002-6893-602X]; Bacmann, A. [0000-0003-1263-4986]Determining the mechanism by which high-mass stars are formed is essential for our understanding of the energy budget and chemical evolution of galaxies. By using the New IRAM KIDs Array 2 (NIKA2) camera on the Institut de Radio Astronomie Millimétrique (IRAM) 30-m telescope, we have conducted high-sensitivity and large-scale mapping of a fraction of the Galactic plane (GP) in order to search for signatures of the transition between the high- and low-mass star-forming modes. Here, we present the first results from the Galactic Star Formation with NIKA2 (GASTON) project, a Large Programme at the IRAM 30-m telescope that is mapping ≈2 deg2 of the inner GP, centred on ℓ = 23∘.9, b = 0∘.05, as well as targets in Taurus and Ophiuchus in 1.15- and 2.00-mm continuum wavebands. In this paper, we present the first of the GASTON GP data taken, and present initial science results. We conduct an extraction of structures from the 1.15-mm maps using a dendrogram analysis and, by comparison to the compact source catalogues from Herschel survey data, we identify a population of 321 previously undetected clumps. Approximately 80 per cent of these new clumps are 70-μm-quiet, and may be considered as starless candidates. We find that this new population of clumps are less massive and cooler, on average, than clumps that have already been identified. Further, by classifying the full sample of clumps based upon their infrared-bright fraction – an indicator of evolutionary stage – we find evidence for clump mass growth, supporting models of clump-fed high-mass star formation.Publicación Acceso Abierto The miniJPAS survey: star-galaxy classification using machine learning(EDP Sciences, 2021-01-18) Baqui, P. O.; Marra, V.; Casarini, L.; Angulo, R.; Hernández Monteagudo, C.; Lopes, P. A. A.; López Sanjuan, C.; Muniesa, D. J.; Placco, V. M.; Quartin, M.; Queiroz, C.; Sobral, D.; Tempel, E.; Varela, J.; Vílchez, J. M.; Abramo, L. R.; Alcaniz, J. S.; Benítez, N.; Bonoli, S.; Carneiro, S.; Cenarro, A. J.; Cristóbal Hornillos, D.; De Amorim, A. L.; De Oliveira, C. M.; Dupke, R. A.; Ederoclite, A.; González Delgado, R. M.; Marín Franch, A.; Moles, M.; Vázquez Ramió, H.; Sodré, L.; Taylor, K.; Solano, Enrique; Díaz García, Pedro; European Commission (EC); Agencia Estatal de Investigación (AEI); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Gobierno de Aragón; Ministerio de Ciencia e Innovación (MICINN); Ministerio de Economía y Competitividad (MINECO); Ministry of Education, Culture, Sports, Science and Technology (MEXT); 0000-0002-7773-1579Context. Future astrophysical surveys such as J-PAS will produce very large datasets, the so-called “big data”, which will require the deployment of accurate and efficient machine-learning (ML) methods. In this work, we analyze the miniJPAS survey, which observed about ∼1 deg2 of the AEGIS field with 56 narrow-band filters and 4 ugri broad-band filters. The miniJPAS primary catalog contains approximately 64 000 objects in the r detection band (magAB ≲ 24), with forced-photometry in all other filters. Aims. We discuss the classification of miniJPAS sources into extended (galaxies) and point-like (e.g., stars) objects, which is a step required for the subsequent scientific analyses. We aim at developing an ML classifier that is complementary to traditional tools that are based on explicit modeling. In particular, our goal is to release a value-added catalog with our best classification. Methods. In order to train and test our classifiers, we cross-matched the miniJPAS dataset with SDSS and HSC-SSP data, whose classification is trustworthy within the intervals 15 ≤ r ≤ 20 and 18.5 ≤ r ≤ 23.5, respectively. We trained and tested six different ML algorithms on the two cross-matched catalogs: K-nearest neighbors, decision trees, random forest (RF), artificial neural networks, extremely randomized trees (ERT), and an ensemble classifier. This last is a hybrid algorithm that combines artificial neural networks and RF with the J-PAS stellar and galactic loci classifier. As input for the ML algorithms we used the magnitudes from the 60 filters together with their errors, with and without the morphological parameters. We also used the mean point spread function in the r detection band for each pointing. Results. We find that the RF and ERT algorithms perform best in all scenarios. When the full magnitude range of 15 ≤ r ≤ 23.5 is analyzed, we find an area under the curve AUC = 0.957 with RF when photometric information alone is used, and AUC = 0.986 with ERT when photometric and morphological information is used together. When morphological parameters are used, the full width at half maximum is the most important feature. When photometric information is used alone, we observe that broad bands are not necessarily more important than narrow bands, and errors (the width of the distribution) are as important as the measurements (central value of the distribution). In other words, it is apparently important to fully characterize the measurement. Conclusions. ML algorithms can compete with traditional star and galaxy classifiers; they outperform the latter at fainter magnitudes (r ≳ 21). We use our best classifiers, with and without morphology, in order to produce a value-added catalog.
