Seminars – Second Semester 2020 > Seminars – Second Semester 2020

Seminars – Second Semester 2020

+ - INVERSE COLORS
Date Speaker Title/Abstract Location
Friday
01/10

11:30am
Chiaki Kobayashi

University of Hertfordshire

The Origin of the Elements and their Evolution in Galaxies

Stars are fossils that retain the history of their host galaxies. At the end of their lives, some explode as supernovae, producing heavy elements that are distributed into the surrounding interstellar gas. New stars that are created from this gas contain the elements that were produced from the previous generations of stars. From the spatial distribution of elements, it is therefore possible to constrain star formation and chemical enrichment histories of the host galaxies. This approach, Galactic Archaeology, has been popularly used for our Milky Way Galaxy. It can also be applied to external galaxies thanks to the recent and future observations with integral field units. My team has been running hydrodynamical simulations from cosmological initial conditions including detailed chemical enrichment. First of all, I will summarize the origin of elements and how well theoretical models can explain the observational data in the Milky Way. Then using chemodynamical simulations, I will discuss the physical process that shaped the structure of the Milky Way: bulge, think disk, thick disk, and halo. Finally, I will show the predictions of cosmic chemical enrichment that can be tested with future observations such as with the James Webb Space Telescope.

Meeting Room of the Núcleo and Zoom
Friday
29/10

11:30am
José Luis Prieto

UDP

Observational constraints on the progenitors and explosion mechanisms of supernovae and other transients Meeting Room of the Núcleo and Zoom
Friday
12/11

11:30am
Alessia Tortosa

UDP

The extreme properties of the nearby hyper-Eddington accreting Active Galactic Nucleus in IRAS 04416+1215

The physical properties of the accretion flow and of the X-ray emitting plasma, in supermassive black holes accreting at extreme Eddington rates, are still very unclear and it is still largely debated what are the physical properties of the accretion flow and of the X-ray source in this regime. I will present the analysis of simultaneous XMM-Newton and NuSTAR observations of the hyper-Eddington Seyfert 1 galaxy IRAS 04416+1215. IRAS 04416+1215 is part of the SEAMBHs sample, which includes objects studied with a dedicated reverberation mapping campaign, and it has one of the highest Eddington ratio in the local Universe. The main goal of these observations was to investigate the properties of the X-ray corona, as well as the structure of the accretion flow and of the circumnuclear environment, in this regime of extreme accretion.

Meeting Room of the Núcleo and Zoom
Friday
22/11

11:30am
Lucas Cieza
UDP
The Ph.D. Program in Astrophysics at Universidad Diego Portales

Postponed until January.

Meeting Room of the Núcleo and Zoom
Friday
03/12

11:30am
Dary Ruíz-Rodríguez
NRAO
A Chemical and Physical Approach to the Evolution from Protoplanetary Disks to Protostellar Outflows
Winds and outflows are fundamental ingredients of star and planet formation. The energetics of outflows from young stellar objects (YSOs) are intimately connected to YSO accretion and ultimately set the initial conditions for protoplanetary disk evolution. The physical and chemical structure of the disk itself may be sharply and drastically altered by outburst events associated with episodic YSO accretion. On larger scales, the molecular chemistry in the environments of YSOs is likely strongly affected by shocks at the working surfaces of the energetic outflows as well as by X-ray emission produced as a consequence of fast YSO accretion episodes and/or YSO magnetic activity. In this talk, I will present a brief review of the demographic millimeter surveys of circumstellar disks transitioning to recent observations of the chemistry of planet-forming regions and molecular outflows, with the ultimate goal of distinguishing between chemistry induced by outflow energetics (shocks) vs. by high energy radiation (X-rays). To illustrate the potential of this approach, I describe my work on interferometric imaging of gas and dust in YSO outflows and individual star/disk systems.
Meeting Room of the Núcleo and Zoom
Friday
10/12

11:30am
Claudia Aguilera
UDP
Meeting Room of the Núcleo and Zoom