The AGN-obscuring Torus: The End of the ``Doughnut'' Paradigm?

@article{Elitzur2006TheAT,
  title={The AGN-obscuring Torus: The End of the ``Doughnut'' Paradigm?},
  author={Moshe Elitzur and Isaac Shlosman},
  journal={The Astrophysical Journal},
  year={2006},
  volume={648}
}
Unified schemes of active galactic nuclei (AGNs) require an obscuring dusty torus around the central engine. The compact sizes (only a few parsecs) determined in recent high-resolution observations require that the obscuring matter be clumpy and located inside the region where the black hole gravity dominates over the galactic bulge. This location is in line with the scenario depicting the torus as the region of the clumpy wind coming off the accretion disk in which the clouds are dusty and… 
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