SEMINAR OF THE DEPARTMENT OF ASTRONOMY
Galaxy evolution at small scales with disrupted Milky Way satellites
by a talk by Guilherme Limberg (IAG-USP e University of Chicago)
Abstract:
Unveiling the driving mechanisms behind galaxy formation and growth is one of the main goals of Astrophysics, from the tinniest ultra-faint dwarfs in the Local Group to the most luminous blue galaxies beyond the epoch of reionization. In this talk, I will demonstrate how we can leverage astrometric and spectroscopic stellar data to learn about galaxy evolution at small scales and connect with extragalactic probes. First, I will show that the disrupted dwarf galaxy responsible for the Milky Way’s last major merger was the original host of ωCentauri, the most massive Galactic globular cluster known to be a former nuclear star cluster. The recent discovery of an intermediate-mass black hole inside ωCentauri thus allows us to extend the relation between stellar mass and central black hole mass to the dwarf galaxy regime. Second, I will present spectroscopic confirmation that the extremely diffuse dwarf Crater II, an extraordinary local analog of ultra-diffuse galaxies, has a stellar stream and, therefore, is experiencing heavy tidal disruption. I will show that Crater II also has an exceptionally low metallicity compared to the local stellar mass—metallicity relation and discuss its implications for the formation of ultra-diffuse galaxies in general. These are the final two results from my PhD thesis which I will be defending in October 2024 at IAG.
Short-Bio:
Guilherme Limberg is a finishing PhD candidate at IAG/USP. Starting October 2024, Guilherme will be an independent postdoctoral fellow at the Kavli Institute for Cosmological Physics (KICP) of the University of Chicago.
Google Meet: https://meet.google.com/pcw-gmem-jyi
Link da transmissão: https://www.youtube.com/c/AstronomiaIAGUSP/live