High-redshift obscured quasars

Alejo Martinez-Sansigre; Steve Rawlings

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arXiv · astro-ph/0701143

High-redshift obscured quasars

Alejo Martinez-Sansigre·Steve Rawlings

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Abstract

Using mid-infrared and radio criteria, we select a sample of candidate z~2 obscured quasars. Optical spectroscopy confirms about half of these as type-2 quasars, and modelling the population suggests 50-80% of the quasars are obscured. We find some flat radio spectrum type-2 quasars, and tentative evidence for obscuration unrelated to the torus. Using a similar sample, we also find evidence for a significant fraction of Compton-thick quasars.

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Alejo Martinez-Sansigre, Steve Rawlings. 2007-01-10. High-redshift obscured quasars. https://arxiv.org/abs/astro-ph/0701143

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