The AGN Source Population in the Chandra Deep Field-North Survey: Constraints from X-ray Spectroscopy and Variability
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چکیده
With the 0.5-10.0 keV background nearly resolved (e.g., Giacconi et al. 2000; Cowie et al. 2002), the emphasis has shifted towards understanding the nature of the faint X-ray population — a clear necessity if we wish to understand the formation and evolution of active galactic nuclei (AGN). Here we report on preliminary spectral and temporal Xray studies of AGN in the 2 Ms Chandra Deep Field-North Survey (CDF-N; D.M. Alexander et al. in prep). Our sample is comprised of 136 CDF-N sources with > 200 net counts (∼30% of the total CDF-N sample), spanning (0.014– 2)× 10 ergs cm s; 72 sources have known redshifts.
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تاریخ انتشار 2002