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تسجيل مستخدم جديدResolving the Hot Dust Disk of ESO323-G77
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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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