From Disks to Dwarfs: Chemodynamics as a Probe of Galaxy Formation in the Local Group

Dr. Ivanna Escala (Carnegie Observatories)
Tuesday, June 7, 2022 - 11:00am

On both large and small scales, galaxies are predicted to form via hierarchical assembly. Disk galaxies similar to the Milky Way grow in part through the accretion of smaller galactic systems, where observations of stellar halos in the local universe show clear evidence in favor of this scenario in the form of stellar streams and shells. However, outstanding questions remain concerning the nature of the stellar halo and its connection to the disk. Moreover, although late-time mergers between dwarf galaxies are predicted to have occurred in the Local Group, comprehensive observational support is lacking for this phenomenon. In this talk, I will highlight the utility of chemodynamical analyses of resolved stars in nearby disk and dwarf galaxies for exploring galaxy formation scenarios in a cosmological context. I will present recent results on M31's last significant merger from Keck/DEIMOS surveys of M31's Giant Stellar Stream and Northeast Shelf. I will also discuss an ongoing spectroscopic effort with Magellan/IMACS targeting isolated Local Group dwarf galaxies with unusual kinematics that may be signatures of dwarf-dwarf interactions. Future facilities will enable similar resolved star chemodynamical studies in a plethora of new disk and dwarf galaxies in the Local Volume.

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