Physics Department Seminar
Dr. Kristine Spekkens
Associate Professor
Royal Military College of Canada
Tuesday, January 22, 2019

Atomic Gas and the Cosmology of Extreme Dwarf Galaxies

Understanding the diversity of nearby galaxies within the cosmological framework that describes the large-scale structure and evolution of the universe is an important research driver in extragalactic astronomy. In that context, the properties of the smallest and faintest ("dwarf") galaxies, which are both hard to observe and susceptible to a variety of competing physical processes because of their shallow gravitational potential wells, are the most challenging to explain. In this talk, I will describe how atomic gas observations with current and future radio telescopes can constrain the origin of some of the most extreme dwarfs known today. I will first focus on how sensitive single-dish observations of ultra-diffuse galaxies are a powerful tool for measuring their structure and distinguishing between competing formation models. Then, I will describe how a widefield atomic gas survey soon to be undertaken with a new radio interferometer in the Australian outback will allow for the first spatially resolved populations studies of the smallest field dwarfs for comparison with cosmological predictions.