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arXiv · 2103.07482

Resolving the Hot Dust Disk of ESO323-G77

James H. Leftley·Konrad R. W. Tristram·Sebastian F. Hönig·Daniel Asmus·Makoto Kishimoto·Poshak Gandhi
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Abstract

Infrared interferometry has fuelled a paradigm shift in our understanding of the dusty structure in the central parsecs of Active Galactic Nuclei (AGN). The dust is now thought to comprise of a hot ($\sim1000\,$K) equatorial disk, some of which is blown into a cooler ($\sim300\,$K) polar dusty wind by radiation pressure. In this paper, we utilise the new near-IR interferometer GRAVITY on the Very Large Telescope Interferometer (VLTI) to study a Type 1.2 AGN hosted in the nearby Seyfert galaxy ESO323-G77. By modelling the squared visibility and closure phase, we find that the hot dust is equatorially extended, consistent with the idea of a disk, and shows signs of asymmetry in the same direction. Furthermore, the data is fully consistent with the hot dust size determined by K band reverberation mapping as well as the predicted size from a CAT3D-WIND model created in previous work using the SED of ESO323-G77 and observations in the mid-IR from VLTI/MIDI.

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James H. Leftley, Konrad R. W. Tristram, Sebastian F. Hönig, Daniel Asmus, Makoto Kishimoto, Poshak Gandhi. 2021-03-12. Resolving the Hot Dust Disk of ESO323-G77. https://doi.org/10.3847/1538-4357%2Fabee80

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