We present broadband properties of sources in the Chandra Deep Field-North ( CDF-N ) with known spectroscopic redshifts .
The high luminosity and high redshift bins are dominated by typical quasars .
The intermediate redshift ( z \sim 0.7 - 1.5 ) and luminosity ranges ( L _ { 0.5 - 8.0 keV } \sim 10 ^ { 42.5 - 43.5 } erg s ^ { -1 } ) show a mix of different source types , with the apparently absorbed objects in the majority .
At the faint flux limit of the CDF-N , a substantial fraction of the detections can be identified as normal/star-forming galaxies at low redshift .
The AGNs in the sample can be subdivided into four classes based upon their rest frame spectral energy distribution : luminous , apparently unabsorbed QSOs ; objects with reddened optical spectra and no signs of X-ray absorption ; apparently X-ray absorbed AGNs with no signs of reddening in their optical spectra ; and optically reddened sources with X-ray spectra indicative of large amounts of obscuration .
We argue that the AGNs of higher luminosity tend to have a lower X-ray absorbing column density , but the ratio of X-ray absorbed to unabsorbed AGNs remains constant with redshift .
We find that the relations between UV and X-ray luminosities derived by Strateva et al .
( 2005 ) and Steffen et al .
( 2006 ) only hold for bright sources , and break down when faint objects in the sample are included .
This is only partly owing to the fact that the majority of the faint sources are absorbed ; several faint sources must also have intrinsically lower X-ray luminosity .
A fit to the NIR-optical-UV broadband SEDs of AGNs allows us to constrain the absorption parameters independently from the X-ray analyses .
We show that the N _ { H } values derived by the X-ray and optical methods are not correlated .
This may be because the X-ray absorption and optical attenuation do not originate at the same location , and/or the dust properties responsible for the optical attenuation in AGNs are very different from the locally known dust properties .