Colloquium:Dr.Mitchell Revalski|Space Telescope Science Inst
In-Person PHYS 401
Wednesday, September 13, 2023 · 11 AM - 12 PM
TITLE: How Supermassive Black Hole Winds Shape Galaxies in the Local Universe
ABSTRACT: Active galactic nuclei (AGN) can launch powerful outflows of ionized gas, and spatially-resolved observations are required to fully understand their role in galaxy evolution. Studies using the Hubble Space Telescope (HST) have revolutionized our understanding in this area, but open questions linger: How common are outflows, what mechanisms drive them, where are they launched from, and how far do they extend into their host galaxies? Furthermore what are the most accurate techniques for measuring their energetic impact? I will describe our efforts to answer these questions for the ionized outflows in nearby active galaxies. Using spatially-resolved spectroscopy from HST and ground-based facilities, we have modeled the geometry and kinematics of these systems and found outflows in at least half of the galaxies, whose kinematics are consistent with radiatively driven gas that is launched from multiple radii. We have also generated photoionization models to precisely measure gas masses and outflow rates, which constrain the energetic impact of the outflows on their host galaxies. These studies are providing insight into the range of densities and ionization within the outflows, which we are using to create models that include the more highly ionized X-ray gas in order to build a more complete picture of AGN feedback in the local Universe.
ABSTRACT: Active galactic nuclei (AGN) can launch powerful outflows of ionized gas, and spatially-resolved observations are required to fully understand their role in galaxy evolution. Studies using the Hubble Space Telescope (HST) have revolutionized our understanding in this area, but open questions linger: How common are outflows, what mechanisms drive them, where are they launched from, and how far do they extend into their host galaxies? Furthermore what are the most accurate techniques for measuring their energetic impact? I will describe our efforts to answer these questions for the ionized outflows in nearby active galaxies. Using spatially-resolved spectroscopy from HST and ground-based facilities, we have modeled the geometry and kinematics of these systems and found outflows in at least half of the galaxies, whose kinematics are consistent with radiatively driven gas that is launched from multiple radii. We have also generated photoionization models to precisely measure gas masses and outflow rates, which constrain the energetic impact of the outflows on their host galaxies. These studies are providing insight into the range of densities and ionization within the outflows, which we are using to create models that include the more highly ionized X-ray gas in order to build a more complete picture of AGN feedback in the local Universe.