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Title: An image of the dust sublimation region in the nucleus of NGC 1068
We present near-infrared interferometric data on the Seyfert 2 galaxy NGC 1068, obtained with the GRAVITY instrument on the European Southern Observatory Very Large Telescope Interferometer. The extensive baseline coverage from 5 to 60 M λ allowed us to reconstruct a continuum image of the nucleus with an unrivaled 0.2 pc resolution in the K -band. We find a thin ring-like structure of emission with a radius r  = 0.24 ± 0.03 pc, inclination i  = 70 ± 5°, position angle PA = −50 ± 4°, and h / r  <  0.14, which we associate with the dust sublimation region. The observed morphology is inconsistent with the expected signatures of a geometrically and optically thick torus. Instead, the infrared emission shows a striking resemblance to the 22 GHz maser disc, which suggests they share a common region of origin. The near-infrared spectral energy distribution indicates a bolometric luminosity of (0.4–4.7) × 10 45 erg s −1 , behind a large A K  ≈ 5.5 ( A V  ≈ 90) screen of extinction that also appears to contribute significantly to obscuring the broad line region.
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Astronomy & Astrophysics
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National Science Foundation
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