Gas-Rich Galaxies as Cosmological Probes

Kristine Spekkens
Professor, RMC Physics and Space Science Cross-Appointed, Queen's Physics, Engineering Physics and Astronomy
Canadian Science Director,  Square Kilometer Array

Abstract

The atomic gas (HI) content of nearby galaxies provides important insight into the physics that underpins their formation and evolution within the standard cosmology. In this talk, I will highlight some of my group's recent progress towards building statistical samples of gas-rich galaxies to use as cosmological probes. I will first focus on how sensitive HI searches in optically-selected dwarf and ultra-diffuse galaxy candidates are a powerful tool for measuring their structure and constraining formation models. I will then describe how the widefield WALLABY survey, now underway on the Australian SKA Pathfinder (ASKAP) telescope, is delivering the first spatially-resolved populations of HI disks for comparison with cosmological predictions. I will finish by explaining how this work paves the way for probing HI in galaxies more widely and deeply than ever before with a new generation of radio facilities that are under construction now, including the billion-dollar SKA telescope in which Canada will soon become a full member.

Timbits, coffee, tea will be served in STI A before the colloquium.

Prof. Spekkens will be meeting with members of the department on Tuesday and Wednesday, October 10 and 11.