Colloquium - Kat Barger | Department of Physics

Colloquium - Kat Barger

Event Information
Event Date: 
Tuesday, February 10, 2015 - 3:30pm
Event Location: 
PHYS 104

Feeding the Milky Way through the cannibalization of nearby galaxies: tracking the gas flowing from galaxies in nearby universe

Dr. Kat Barger, Assistant Professor at Texas Christian University

Abstract: The environment that galaxies live in strongly influences their shape, structure, and evolution. Large galaxies, like our own Milky Way, rapidly consume their gas supplies forming stars. The gas clouds that feed our and other galaxies are difficult to track due to their diffuse and ionized nature. Furthermore, gas clouds must travel through harsh environments that can cause them to evaporate in transit before reaching the star-forming disks of galaxies. The gas flows associated with the nearby Magellanic Cloud galaxies provide an advantageous opportunity to study this cycle in detail. Through velocity resolve optical emission-line and UV absorption-line observations of the elusive ionized gas in their surroundings--using the Wisconsin H-alpha Mapper (WHAM) and the Hubble Space Telescope--we determine the origins, properties, and fates of these gas flows. We find that the interacting Magellanic Cloud galaxies have lost over 2/3 of their gas due to galactic winds and tidal processes. This dislodged gas acts as a massive external reservoir that feeds the Milky Way and could solve the long standing mystery of how our Galaxy will feed itself for many billions to come.