Examinando por Autor "Soto, Mario"

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    CAPOS: the bulge Cluster APOgee Survey IV elemental abundances of the bulge globular cluster NGC 6558
    (Oxford University Press, 2023-12-01) González-Díaz, Danilo; Fernández-Trincado, José G.; Villanova, Sandro; Geisler, Doug; Barbuy, Beatriz; Minniti, Dante; Beers, Timothy C.; Bidin, Christian Moni; Mauro, Francesco; Muñoz, Cesar; Tang, Baitian; Soto, Mario; Monachesi, Antonela; Lane, Richard R.; Frelijj, Heinz
    This study presents the results concerning six red giant stars members of the globular cluster NGC 6558. Our analysis utilized high-resolution near-infrared spectra obtained through the CAPOS initiative (the APOgee Survey of Clusters in the Galactic Bulge), which focuses on surveying clusters within the Galactic Bulge, as a component of the Apache Point Observatory Galactic Evolution Experiment II survey (APOGEE-2). We employ the Brussels Automatic Code for Characterizing High accUracy Spectra (BACCHUS) code to provide line-by-line elemental-abundances for Fe-peak (Fe, Ni), α-(O, Mg, Si, Ca, Ti), light-(C, N), odd-Z (Al), and the s-process element (Ce) for the four stars with high-signal-to-noise ratios. This is the first reliable measure of the CNO abundances for NGC 6558. Our analysis yields a mean metallicity for NGC 6558 of 〈[Fe/H]〉 = −1.15 ± 0.08, with no evidence for a metallicity spread. We find a Solar Ni abundance, 〈[Ni/Fe]〉 ∼ +0.01, and a moderate enhancement of α-elements, ranging between +0.16 and [removed] +0.99, along with a low level of carbon, [C/Fe] < −0.12. This behaviour of Nitrogen-Carbon is a typical chemical signature for the presence of multiple stellar populations in virtually all GCs; this is the first time that it is reported in NGC 6558. We also observed a remarkable consistency in the behaviour of all the chemical species compared to the other CAPOS bulge GCs of the same metallicity. © The Author(s) 2023.
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    Como influye la preparación académica de los padres en el desempeño en el sector matemáticas de los alumnos de 5° año del Liceo Volcán San José
    (Universidad Andrés Bello, 2012) Castañón, Bárbara; Escobar, César; Terán, Francis; Soto, Mario; Facultad de Humanidades y Educación; Escuela de Educación
    En el presente trabajo, tras un análisis cuantitativo y cualitativo de diferentes instrumentos de orden estadístico, como son el libro de clases, las fichas de los alumnos y las gráficas desarrolladas a partir de encuestas aplicadas a los apoderados como a los alumnos, se busó identificar la relación existente entre el nivel educacional de los apoderados y el rendimiento que demuestran los alumnos en el sector de matemática en los quintos básicos del Liceo El Volcán San José en la comuna de Puente Alto . Luego de cotejar estos datos en forma cuantitativa, con algunas referencias teóricas, y el análisis de los mismos, aplicamos algunos elementos de la estadística para obtener resultados que nos lleven a obtener datos comparativos entre ambos factores de estudio: educación de los padres y rendimiento de los alumnos en Matemática, verificando si existe o no una relación directa, o influencia entre ambas variables. Los datos arrojados por este análisis y llevados a gráficos nos conducen a establecer si existe o no una relación entre éstos factores, en este sector de aprendizaje y nivel. Para conocer en detalle la investigación, así como las conclusiones que se desprenden de éste estudio se invita a revisar el trabajo.
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    Galaxy clustering in the VVV near-IR galaxy catalogue
    (Oxford University Press, 2022-06-01) Soto, Mario; Sgró, Mario A.; Baravalle, Laura D.; Alonso, M. Victoria; Nilo Castellón, José Luis; Valotto, Carlos; Taverna, Antonela; Díaz-Giménez, Eugenia; Villalón, Carolina; Minniti, Dante
    Mapping galaxies at low Galactic latitudes and determining their clustering status are fundamental steps in defining the large-scale structure in the nearby Universe. The VISTA Variables in the Vía Láctea (VVV) near-IR galaxy catalogue (VVV NIRGC) allows us to explore this region in great detail. Our goal is to identify galaxy overdensities and characterize galaxy clustering in the Zone of Avoidance. We use different clustering algorithms to identify galaxy overdensities: the Voronoi tessellations, the minimum spanning tree, and the ordering points to identify the clustering structure. We studied the membership, isolation, compactness, and flux limits to identify compact groups of galaxies. Each method identified a variety of galaxy systems across the Galactic plane that are publicly available. We also explore the probability that these systems are formed by concordant galaxies using mock catalogues. 19 galaxy systems were identified in all of the four methods. They have the highest probability to be real overdensities. We stress the need for spectroscopic follow-up observations to confirm and characterize these new structures. © 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.
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    The VVV near-IR galaxy catalogue beyond the Galactic disc
    (Monthly Notices of the Royal Astronomical Society, 2021-03) Baravalle, Laura D; Alonso, María Victoria; Minniti, Dante; Nilo Castellón, José Luis; Soto, Mario; Valotto, Carlos; Villalón, Carolina; Graña, Darío; Amôres, Eduardo B; Milla Castro, Fernanda
    Knowledge about the large-scale distribution of galaxies is far from complete in the Zone of Avoidance (ZoA), which is mostly due to high interstellar extinction and to source confusion at lower Galactic latitudes. Past near-infrared (NIR) surveys, such as the Two Micron All Sky Survey (2MASS), have shown the power of probing large-scale structure at these latitudes. Our aim is to map the galaxy distribution across the Southern Galactic plane using the VISTA Variables in the Vía Láctea Survey (VVV), which reach 2-4 mag deeper than 2MASS. We used SExtractor+PSFEx to identify extended objects and to measure their sizes, the light concentration index, magnitudes, and colours. Morphological and colour constraints and visual inspection were used to confirm galaxies. We present the resulting VVV NIR Galaxy Catalogue (VVV NIRGC) of 5563 visually confirmed galaxies, of which only 45 were previously known. This is the largest catalogue of galaxies towards the Galactic plane, with 99 per cent of these galaxies being new discoveries. We found that the galaxy density distribution closely resembled the distribution of low interstellar extinction of the existing NIR maps. We also present a description of the 185 2MASS extended sources observed in the region, of which 16 per cent of these objects had no previous description, which we have now classified. We conclude that interstellar extinction and stellar density are the main limitations for the detection of background galaxies in the ZoA. The VVV NIRGC is a new data set providing information for extragalactic studies in the Galactic plane. © 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.