A Complete Census of the Properties of Radio-Quiet AGN in the Local Universe: Implications for Black Holes and AGN Feedback

Abstract:

Active Galactic Nuclei (AGN) are among the most energetic objects in the Universe, powered by accretion onto supermassive black holes. Despite decades of study, many questions remain about how AGN generate radio emission and interact with their host galaxies. In this talk, I will present results from three radio studies of nearby AGN. First, I will discuss the final phase of the largest 22 GHz, 1” resolution imaging survey of 231 nearby Swift-BAT selected AGN. We find a wide range of radio morphologies and show that the compact radio cores are consistent with coronal emission, while the extended emission is largely associated with star formation. Next, I will present radio spectral energy distributions for 100 AGN spanning frequencies from tens of MHz to hundreds of GHz. Using a Bayesian modeling framework, we find that fewer than half of the sources are well described by a simple power law, highlighting the complexity of AGN radio emission and the need for broad frequency coverage to uncover the physical processes shaping AGN spectra. Finally, I will present high-resolution VLA observations of a water maser in the Seyfert 2 galaxy NGC 1106. Rather than originating in the accretion disk, we localize the maser approximately one kpc from the nucleus, where it is likely produced by an interaction between an AGN-driven outflow and the surrounding interstellar medium. Together, these results provide new insights into the origin of radio emission in AGN and the ways in which AGN interact with their host galaxies.

Please note that this colloquium will be held in the Marsfield Lecture theatre

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