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AGN predictions for the Hubble Deep Field and the X-ray background

O. Almaini·A. C. Fabian
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Abstract

We estimate the number of AGN among the galaxies in the Hubble Deep Field (HDF). The recent discovery of a class of X-ray luminous narrow emission-line galaxies has provided a possible explanation for the origin of the X-ray background (XRB), although the nature of the activity is still unresolved. By extrapolating the observed X-ray number count distribution to faint optical magnitudes we predict that this AGN population could account for a significant fraction, $\sim 10$ per cent, of the galaxies in the HDF. In contrast, normal broad line QSOs are expected to account for no more than $\sim 0.1$ per cent of the sources at these magnitudes.

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O. Almaini, A. C. Fabian. 1997-04-14. AGN predictions for the Hubble Deep Field and the X-ray background. https://doi.org/10.1093/mnras%2F288.1.l19

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