University of Minnesota
School of Physics & Astronomy

Physics and Astronomy Calendar

Friday, February 19th 2016
2:30 pm:
MIFA Colloquium in 331 Smith Hall
Speaker: Ryan Tanner, UNC
Subject: Galactic Filaments: Pathways for Cold Gas in Galactic Winds

Starburst driven superbubbles can produce large scale galactic outflows. Embedded in these outflows are optically bright filaments containing cold, dense gas. These filaments are the main source of warm and cold gas being transported into the circumgalactic medium. Motivated by Herschel and Hubble observations of cold gas in galactic filaments I model starburst driven galactic winds and include a radiative cooling prescription with cooling down to 10 K. This allows me to investigate the structure and dynamics of filaments in a galactic wind. Optically bright filaments form at the edge of merging superbubbles and if anchored to a star forming complex will persist and grow to > 500 pc in length. The warm and cold gas contained in the filaments moves much slower than the surrounding hot, diffuse galactic wind, with the coldest gas hardly moving with respect to the galaxy. Using synthetic absorption profiles I can probe different temperature regimes and measure the velocity of the cold, warm and hot gas phases. Warm and cold gas embedded in the galactic wind show asymmetric absorption profiles consistent with observations and theoretical predictions. These asymmetries can be used to infer the kinematics of the filaments and associated dense cores.

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