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Session 109 - Seyferts.
Oral session, Thursday, January 16
Piers 4/5,

[109.05] VLBA + VLA Radio Continuum Imaging of the Parsec-Scale Torus in NGC 1068

J. F. Gallimore (MPE), S. A. Baum, C. P. O'Dea (STScI)

We have imaged the low surface brightness radio continuum source, component S1, associated with the brighter water masers of the Seyfert nucleus of NGC 1068. S1, roughly 1 pc in length and 0.5 pc wide, resolves into clumps aligned nearly perpendicular to the local radio jet axis. The peak brightness temperature is roughly 4\times 10^6 K, and there is structure down to the detection limit, roughly 2\times 10^5 K. It is likely that thermal free-free processes dominate the radio continuum emission from this region. There are, in addition, broad, spatial correspondences between the water maser and the radio continuum emission. We argue that S1 is actually the inner, ionized region of the molecular torus proposed to obscure the central engine. The result of simple photoionization calculations is that the torus receives a smaller flux of ionizing photons that does the engine. The result of simple photoionization calculations is that the torus receives a smaller flux of ionizing photons that does the narrow-line region. The implications are that the torus may be patchy, so that some UV photons leak deeper into the torus, with th


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