Líneas de Investigación
Astrofísica estelar
Una de las áreas de investigación consolidadas del GAULS, los investigadores del grupo de astrofísica estelar centran su trabajo en la búsqueda y entendimiento de las propiedades de la componente estelar de la Vía Láctea, y las trazas evolutivas que definen la estructura galáctica. Entre las principales líneas de investigación destacan:

  • Estudio de regiones de formación estelar galáctica.
  • Fotometría y espectroscopía de estrellas de alta masa.
  • Estudios sistemáticos temporales de estrellas variables.
  • Relevamientos infrarrojos de estrellas masivas y regiones de formación estelar densas.

  • Investigadores

  • Dr. Rodolfo Barbá
  • Dra. Julia Arias
  • Dr. Alexandre Román Lópes
  • Dra. Carolina Sabín San Julián
  • Dra. Verónica Firpo

  • Estudiantes de postgrado:
    Estudiante Director
    Piera Soto King Dr Rodolfo Barbá
    Jaime Villaseñor Dr. Rodolfo Barbá
    Natalie Ulloa Dra. Julia Arias
    Abdo Campillay Dra. Julia Arias
    Jaqueline Serón Dr. Alexandre Román
    Jaime Vargas Dr. Alexandre Román

    Astronomía extragaláctica
    Una de las áreas con mayor desarrollo en los últimos años en el GAULS. Los investigadores del área aprovechan al máximo los recursos tecnológicos existente en nuestro país para analizar la interacción de las galaxias en el Universo local, con el fin de aplicar estos conocimientos al entendimiento de la estructura en gran escala del Universo.

  • Cinemática y formación estelar en galaxias en interacción.
  • Cinemática y quimodinámica de regiones HII gigantes.
  • Evolución morfológica de galaxias en sistemas de galaxias.
  • Evolución y estructura de cúmulos de galaxias.
  • Fotometría y espectroscopía de supercúmulos de galaxias.

  • Investigadores

  • Dr. Sergio Torres Flores
  • Dra. Amelia Ramirez
  • Dr. Hector Cuevas Larenas
  • Dr. Carlos López Caravallo
  • Dr. José Luis Nilo Castellón

  • Estudiantes de postgrado
  • Mayte Alfaro. Director Dr. Sergio Torres Flores.
  • Unidad de estudios del espacio cercano
    El más reciente emprendimiento del GAULS. Desde el año 2014 y gracias a una alianza estratégica entre el Departamento de Física y Astronomía de la Universidad de La Serena y la United States Air Force Academy (USAFA), investigadores del GAULS comienzan el estudio de fuentes espaciales artificiales en conjunto a una red mundial de telescopios, con el fin de crear un mapa sin precedentes, de los objetos que circundan nuestro planeta.

  • Espectroscopía de satélites artificiales.
  • Determinación de parámetros orbitales de satélites artificiales.

  • Investigadores

  • Dra. Amelia Ramírez.
  • Dr. José Luis Nilo Castellón.

  • Publicaciones Científicas Indexadas
    Publicaciones 2015
  • "Low X-ray Luminosity Galaxy Clusters. III: Weak Lensing Mass Determination at 0.18 < z < 0.70."i>
    GonzalezGael,E.; Foex, G.; Nilo Castellón,J.L.; Domínguez Romero, M.; Alonso. M.V.; García Lambas,D.; Moreschi, O.; Gallo, E.

  • "Rotation, spectral variability, magnetic geometry and magnetosphere of the Of?p star CPD -28° 2561"
    Wade, G. A.; Barbá, R. H.; Grunhut, J.; Martins, F.; Petit, V.; Sundqvist, J. O.; Townsend, R. H. D.; Walborn, N. R.; Alecian, E.; Alfaro, E. J.; Apellániz, J. Maíz; Arias, J. I.; Gamen, R.; Morrell, N.; Nazé, Y.; Sota, A.; ud-Doula, A.; the MiMeS Collaboration

  • "Witnessing Gas Mixing in the Metal Distribution of the Hickson Compact Group HCG 31"i>
    Torres-Flores, S.; Mendes de Oliveira, C.; Amram, P.; Alfaro-Cuello, M.; Carrasco, E. R.; de Mello, D. F.

  • "Hundreds of New Cluster Candidates in the VISTA Variables in the V ́ıa Lactea Survey DR1"i>
    Barbá, R. H. ; Román Lópes, A.; Nilo Castellón, J.L.; Firpo, V.; Minniti,D; And other 6 authors

  • "Orbital and Physical Properties of the σ Ori Aa, Ab, B Triple System"i>
    Simón-Díaz, S.; Caballero, J. A.; Lorenzo, J.; Maíz Apellániz, J.; Schneider, F. R. N.; Negueruela, I.; Barbá, R. H.; Dorda, R.; Marco, A.; Montes, D.; Pellerin, A.; Sanchez-Bermudez, J.; Sódor, Á.; Sota, A.


  • Note: Only refereed articles are considered in the list.For all 2015 bibliographic sources click here.
    Publicaciones 2014


    Proyectos científicos en ejecución, 2015.
    Dirección de Investigación Universidad de La Serena
  • Amelia Ramírez . Pares de galaxias elípticas y su relación con el medio ambiente galáctico. (PR13142)
  • Héctor Cuevas . Evolución Morfológica de galaxias en cúmulos de baja Luminosidad en rayos-X. (PR13143)
  • Alexandre Román . Spectroscopic Survey of Galactic Massive stellar Candidates: Westerlund 2 and NGC3603. (PR13144)
  • Fondecyt
  • “Investigating the properties of massive stars throught dedicated spectroscopic and imaging surveys”. FONDECYT Regular 1140076, PI. Dr. Rodolfo Barbá.
  • "Toward the understanding of the early evolution of massive stars: detailed quantitative analyses of ZAMS O-star candidates". Fondecyt Iniciación 11121550. PI. Dra. Julia Arias.
  • Comité Mixto
    Gemini-Conicyt
    Post-doctorados
  • ESO-Comité mixto 2013-2015. P.I. del proyecto Dr. Rodolfo Barbá. Investigador ejecutante: Dra. Verónica Firpo.
  • ESO-Comité mixto 2014-2016. P.I. del proyecto Dr. Rodolfo Barbá. Investigador ejecutante: Dra. Carolina Sabin San Julian.
  • USAFA-Falcon Telescope Network 2015-2017. P.I. del proyecto Dra. Amelia Ramírez Rivera. Investigador ejecutante: Dr. José Luis Nilo Castellón


  • Science.Astro.Userena (SAU)
    Science.Astro.Userena (SAU) is an initiative of the Astronomy Group of the Universidad de La Serena, created to improve the access to the international astronomical community, to the observational data base in which the astronomers of the group have been based their research in the last 10 years.
    SAU provides photometric and spectroscopical data taken in some of the most advance optical and infrared telescopes in the world, as well as an increasing number of catalogues, already acepted in some of the most prestigious astronomical journals.
    The first version of SAU has just been put online (March 2015) and is mainly founded by proyecto FONDECYT N°1140076, “Investigating the properties of massive stars through dedicated spectroscopic and imaging surveys" (PI: Rodolfo Barbá).

    Hundreds of New Cluster Candidates in the DR1 of the VISTA Variables in the Vía Lactea Survey (Barbá et al. 2015)
    Abstract
    VISTA Variables in the V\'{\i}a L\'actea is an ESO Public survey dedicated to scan the bulge and an adjacent portion of the Galactic disk in the Fourth Quadrant using the VISTA telescope and the near-infrared camera VIRCAM. One of the leading goals of the VVV survey is to contribute to the knowledge of the star cluster population of the Milky Way.
    In order to improve the census of the Galactic star clusters, we performed a systematic and careful scan of the J,H,Ks images of the Galactic Plane section of the VVV survey.
    Our detection procedure is based on a combination of superficial density maps and visual inspection of promising features in the J, H and Ks band images. The material examined are VVV JHKs color-composite images corresponding to the Data Release 1 of VVV.
    We report the discovery of 493 new infrared star cluster candidates. The analysis of the spatial distribution show that the clusters are very concentrated to the Galactic Plane, presenting some local maxima around the position of large star-forming complexes, like G305, RCW95, RCW106, etc. The vast majority of the new star cluster candidates are quite compact and generally surrounded by bright and/or dark nebulosities. IRAS point sources are associated with 59% of the sample, while 88% are associated with MSX point sources. GLIMPSE 8 micron images of the cluster candidates show a variety of morphologies, 292 clusters being dominated by knotty sources, while 361 clusters show some kind of nebulosity at this wavelength regime. Spatial cross-correlation with young stellar objects, masers, and extended green objects catalogues suggest that a large sample of the new cluster candidates are extremely young. In particular, 104 star clusters associated to methanol masers, which are excellent candidates for ongoing massive star formation. Also, there is a special set of sixteen cluster candidates which present clear signspot of star forming activity having associated simultaneosly dark nebulae, young stellar objects, extended green objects and masers.
    Members
    Rodolfo H. Barbá (P.I.)1,†
    A. Roman-Lopes 1,
    J. L. Nilo Castellón1,
    V. Firpo1,
    D. Minniti2,3,4,5,6,
    P. Lucas7,
    J.P. Emerson8,
    M. Hempel2,6,
    M. Soto1,9,
    R.K. Saito10.


    (1) Departamento de Física, Universidad de la Serena, Av. Juan Cisternas 1200 Norte, La Serena, Chile.
    (2) Departamento de Ciencias Físicas, Universidad Andres Bello, República 220, Santiago, Chile. %
    (3) Vatican Observatory, Vatican City State V-00120, Italy.
    (4) European Southern Observatory, Vitacura 3107, Santiago, Chile.
    (5) Department of Astrophysical Sciences, Princeton University, Princeton NJ 08544-1001, USA.
    (6) The Milky Way Millennium Nucleus, Av. Vicu\~na Mackenna 4860, 782-0436 Macul, Santiago, Chile.
    , (7) Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Hatfield, AL10 9AB, UK.
    (8) Astronomy Unit, School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London, E1 4NS, UK.
    (9) Space Telescope Science Institute, MD 21117, USA.
    (10) Universidade Federal de Sergipe, Departamento de F\'isica, Av. Marechal Rondon s/n, 49100-000, S\~ao Crist\'ov\~ao, SE, Brazil
    † rbarba [at] userena $dot$ cl. rbarba [at] dfuls $dot$ cl


    Data

    Low X-Ray Luminosity Galaxy Clusters. (Nilo Castellón et al. 2014)
    Abstract
    This is the second of a series of papers on low X-ray luminosity galaxy clusters, in which we present the r′, g′ and i′ photometry obtained with GMOS-IMAGE at Gemini North and South telescopes for seven systems in the redshift range of 0.18 to 0.70. Optical magnitudes, colours and morphological parameters, namely, concentration index, ellipticity and visual morphological classification, are also given. At lower redshifts, the presence of a well-defined red cluster sequence extending by more than 4 magnitudes showed that these intermediate-mass clusters had reached a relaxed stage. This was confirmed by the small fraction of blue galaxy members observed in the central regions of ∼ 0.75 Mpc. In contrast, galaxy clusters at higher redshifts had a less important red cluster sequence. We also found that the galaxy radial density profiles in these clusters were well fitted by a single power law. At 0.18 < z < 0.70, we observed an increasing fraction of blue galaxies and a decreasing fraction of lenticulars, with the early-type fraction remaining almost constant. Overall, the results of these intermediate-mass clusters are in agreement with those for high mass clusters.
    Members
    José Luis Nilo Castellón, M. Victoria Alonso, Diego García Lambas, Ana Laura O' Mill, Carlos Valotto, E. Rodrigo Carrasco, Héctor Cuevas \& Amelia Ramírez
    1 : Instituto de Astronom´ıa Te´orica y Experimental, (IATE-CONICET), Laprida 922, C´ordoba, Argentina.
    2 : Departamento de F´ısica, Facultad de Ciencias, Universidad de La Serena, Cisternas 1200, La Serena, Chile.
    3 : Observatorio Astron´omico de C´ordoba, Universidad Nacional de C´ordoba, Laprida 854, C´ordoba, Argentina.
    4 : Instituto de Astronomia, Geof´ısica e Ciˆencias Atmosf´ericas da USP, Rua do Mat˜ao 1226, Cidade Universit´aria, 05508-090, S˜ao Paulo, Brazil.
    5 : Gemini Observatory/AURA, Southern Operations Center, Casilla 603, La Serena, Chile
    Data