The Dynamic Interstellar Medium

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The interstellar medium (ISM) mediates the evolution of galaxies as the reservoir of material for future star formation and the repository for energy and matter fed back by star formation processes. I use both observations and computer simulations to build a picture of the physical processes in the diffuse ISM which connect star formation at small scales to galaxies at large scales. My work is closely tied to the Dominion Radio Astrophysical Observatory (DRAO). I am an active member of the Canadian Hydrogen Intensity Mapping Experiment (CHIME) cosmology team. CHIME aims to detect hydrogen from when the Universe was about half its present age but must look through the Milky Way, the galaxy we live in. In order to remove this foreground, we must understand it, so I contribute to the cosmology mission through my work on Milky Way science with CHIME. Over the next five years, CHIME will provide a data set which enables unprecedented studies of the Milky Way, producing three-dimensional images of the Galactic magnetic field. I will also be a leader in the scientific use of a major upgrade to the DRAO Synthesis Telescope, enabling a wideband system to produce science that is a successor to the wildly successful Canadian Galactic Plane Survey. I will use this new system to produce an arcminute-resolution counterpart to the CHIME magnetic field survey, probing the star forming regions in the Galactic plane. The upgrade will also enable us to use dozens of radio recombination lines to map diffuse ionized gas throughout the Galactic plane, tracing the energy flow from massive stars through the Galaxy. In my simulations, I incorporate the physics that are relevant to the diffuse ISM, namely heating from stars, thermal and kinetic energy injection from supernovae, radiative cooling, and vertical gravity. This establishes a multi-phase ISM. With this grant, I will incorporate physical processes needed to investigate the vertical support of the different phases of the ISM, with particular focus on the poorly-understood warm ionized phase. All of this work will provide a training ground for highly qualified personnel including undergraduate and graduate students and postdocs. At UBC's Okanagan campus, we are working to build a graduate astrophysics program taking advantage of our geographical proximity and my close scientific ties to DRAO. My students and postdocs will work with the unique expertise of DRAO's scientific and engineering staff. As Canada's national radio astronomy observatory, DRAO has a unique combination of an outstanding radio quiet site and a mission to serve as a training ground for Canada's future radio astronomers and a testbed for new technologies and techniques. My research program uses the unique opportunities afforded by my skill set and my group's ready access to DRAO. We will use these resources to link together the multi-phase interstellar environment to understand how energy and matter are transported within galaxies.