The researchers of the Astronomy Nucleus UDP work in the areas listed below.
Active Galactic Nuclei (AGN)
Observations and simulations of the close environments of accreting supermassive black holes.
Most massive galaxies have at their center supermassive black holes, which play a fundamental role in shaping the properties of their host galaxy during a phase in which they rapidly accrete matter from their surrounding. The structure of this circumnuclear material can be studied in the X-ray band, by looking at the features that are produced by the reprocessing of X-ray photons. By using a new simulations platform the PhD candidate will study how diferent structures of the environments afect the shape of the X-ray radiation. The simulations will then be compared with state-of-the-art observations in order to shed light on the structure of the close environments of supermassive black holes. The development of realistic simulations of the immediate surroundings of black holes is of the utmost importance for future high-resolution spectroscopical X-ray missions such as XARM (to be launched in 2021) and Athena (2028). At UDP, the PhD candidate will join a very dynamic scientific community working on supermassive black holes in Santiago (http://www.agnsantiago.cl).
Hot Dust Obscured Galaxies.
Powered by highly obscured, hyper-luminous AGN activity, Hot Dust Obscured Galaxies are some of the most luminous obscured quasars in the Universe. Identified originally by the WISE mission, these objects have been shown to be in the redshift range 2<z<4 and have luminosities exceeding 10^13 solar luminosities, and about 10% exceeding 10^14 solar luminosities. A possible thesis project will investigate the properties of these objects and their role in galaxy evolution, studying things such as: their merger properties using deep ALMA observations, their redshift evolution, the existence and power of ionized and molecular gas outflows, and their internal gas kinematics, for example.
Galaxy formation and evolution
Since even light takes time to travel, studying distance galaxies allow us look back into the history of the Universe. Also, given the expansion of the Universe, infrared and optical light originating at the dawn of time appears redshifted to longer wavelengths that can be observed by (sub)millimeter
telescopes. At UDP, we offer dissertation topics on galaxy evolution across cosmic time, including: 1) Studies of galaxy evolution through molecular ultra deep field observations (for example, The ALMA Spectroscopic Survey of the Hubble Ultra Deep Field; ASPECS), 2) Investigation of the interstellar medium of distant gravitationally lensed dusty star forming galaxies discovered by the South Pole Telescope, and 3) studies of the properties of normal star forming galaxies at the end of
cosmic reionization with ALMA.
Desde el 2016 realizamos experiencias de difusión astronómica accesibles para personas con discapacidad visual, utilizando modelos táctiles y sonidos, y estableciendo colaboraciones con varias instituciones astronómicas nacionales e internacionales.
Hemos participado en iniciativas que buscan igualar las oportunidades de acceder al conocimiento y el desarrollo científico para todas las personas, como la exhibición de astronomía inclusiva “Inspiring Stars“ de la Unión Astronómica Internacional (IAU) en agosto del 2018, y en octubre del mismo año organizamos la conversación “Las ventajas de la diversidad: participación equitativa e igualitaria en la ciencia“ con la presencia de la astrónoma ciega Wanda Díaz-Merced, con el objetivo de reunir a las comunidades de científicos, educadores y personas con discapacidad.
El 2019 formamos parte de las instituciones que organizaron los eventos del Eclipse Solar Inclusivo, recibiendo y distribuyendo los dispositivos “LightSound 2.0″, donación de la IAU
Actualmente integramos el Nodo Chileno del proyecto IDATA
El proyecto de difusión del Núcleo de astronomía nace el 2015 con charlas y observaciones públicas, redes sociales y página web, y pronto comenzó a ampliarse, según los requerimientos del mismo público.
Actualmente nuestras principales líneas de difusión son la Astronomía Inclusiva y el Arte Astronómico, realizamos visitas a establecimientos escolares, y participamos activamente en eventos nacionales como el Día de la Astronomía, la Semana de la Ciencia y la Temporada de Eclipse Solares, en colaboración con muchas otras instituciones astronómicas.
The Demographics of protoplanetary disks.
Understanding the diversity of the planets that are being formed in the Galaxy requires large surveys of protoplanetary disks in star-forming regions. The closer the region, the higher is the level of detail in the images that can be obtained. The larger the sample, the better the statistics and the chances of finding particularly interesting systems. Such is this context of ODISEA, the Ophiuchus DIsk Survey Employing ALMA, a UDP-led survey of almost 300 protoplanetary disks in the Ophiuchus Molecular Cloud, the closest of the major starforming regions around the Sun. ODISEA aims to investigate the properties of protoplanetary disks as a function of stellar age, mass, and the presence of stellar companion in order to constrain planet formation theories.
Cosmic Dust Laboratory.
While dust typically constitutes only 1% of the mass present in protoplanetary disks, it is the main observable. Since the radiation from disks detected by ALMA mostly originates in cold millimeter-sized grains, correctly interpreting these images requires laboratory measurements of different types of dust grains (silicates, ices and organic material). The UDP Cosmic Dust laboratory is equipped with a top-of-the–line spectrograph that operates between 1 micron and 1 mm, in vacuum and at very cold temperatures (down to 4K) to measure optical properties of cosmic dust under realistic conditions. The measurements from this lab can be applied to models of protoplanetary disks using data from ALMA and other infrared and (sub)millimeter observatories.
Detection and characterization of extrasolar planets
In the last two decades astronomers discovered almost 4000 new worlds around stars other than the Sun. These planets have been discovered with different techniques: transits, radial velocity, microlensing, timing, and high-contrast imaging. Each technique can study a different kind of planet, and all together they are populating the mass/semi-major axis diagram of planetary systems. The huge number of planets discovered is permitting to understand and characterize atmospheres, dynamics, formation, and stability of extrasolar systems. In the last years, many specialized instruments have been built to find and characterize planets as small as our Earth. With instruments as HARPS-S, Espresso (for radial velocity), Trappist-S (transits), OGLE project (microlensing), GPI and SPHERE (direct imaging) and many others, Chile is an ideal place to work as a planet hunter.
Stellar and Galactic astronomy
Supernovae and transients
Explosive stellar transients.
We are in a golden era of transient research, with several panoramic optical surveys now working (e.g., ASAS-SN, GAIA, ATLAS, ZTF) or planned (LSST) that are revolutionizing our understanding of explosive events in the Universe, with applications to several areas of astrophysics such as stellar evolution, chemical enrichment, compact objects, and high energy physics. A PhD student working in this area will be focused in studying explosive stellar transients (e.g., supernovae, tidal disruption events, intermediate luminosity transients), mainly from the All-Sky Automated Survey for Supernovae (ASAS-SN) but also other complete surveys, to constrain their explosion mechanisms, progenitors, and physics through a variety of observational probes.