Abstract
The Chandra and XMM-Newton X-ray observatories have detected obscured active galactic nuclei (AGN) and almost fully resolved the X-ray background into discrete sources. Ground-based observations of the X-ray sources enable the reconstruction of the history of supermassive black hole accretion from the earliest times to the present. A dramatic cosmic downsizing of AGN luminosities is seen at recent times. Correspondingly, the production rate of the AGN radiation drops rapidly, and the dominant period of supermassive black hole production is seen to be at redshifts near z = 1.
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Schedule a callMore From: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
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