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TAPIR Seminar

Friday, March 17, 2023
2:00pm to 3:00pm
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Online and In-Person Event
Physical insights from the smallest galaxies in our Universe
Martin Rey, Beecroft Fellow, Cosmology, University of Oxford,

In person: 370 Cahill -- Attendees joining in person must have a valid Caltech UID.

To Join via Zoom: 864 8902 5566

ABSTRACT: Recent advances in imaging capabilities have transformed our understanding of galaxies at the low surface brightness frontier, unveiling a new population of ever smaller "ultra-faint" dwarf galaxies. Due to their shallow gravitational potential wells, these feeble, low-mass objects are highly sensitive to the physical processes that shape galaxies in our Universe and provide an ideal laboratory for testing galaxy formation models and the nature of dark matter. This same sensitivity, however, also generates extended scatter in their properties and uncertainties in model predictions, which are key to quantify to interpret findings from the current and next generation of deep, wide sky, surveys.

I will showcase results from the new approach of "genetically modified" cosmological simulations of galaxies, which allow us to uniquely separate the role of cosmological assemblies and physical models in a dwarf galaxy's observables. This unique combination of abilities then enables us to extract the expected diversity in the stellar, gaseous and dark matter properties of the faintest galaxies in our Universe. I will then highlight how faint dwarf galaxies can be used to provide new, powerful constraints on stellar evolution models in extreme, low-metallicity environments, and flag remaining modelling uncertainties to be tackled in the coming years.

For more information, please contact JoAnn Boyd by phone at 626-395-4280 or by email at [email protected].