The AGN Source Population in the Chandra Deep Field-North Survey: Constraints from X-ray Spectroscopy and Variability

F. E. Bauer; C. Vignali; D. M. Alexander; W. N. Brandt; G. P. Garmire; A. E. Hornschemeier; P. Broos; L. Townsley; D. P. Schneider

doi:10.1002/asna.200310074

arXiv · astro-ph/0210310

The AGN Source Population in the Chandra Deep Field-North Survey: Constraints from X-ray Spectroscopy and Variability

F. E. Bauer·C. Vignali·D. M. Alexander·W. N. Brandt·G. P. Garmire·A. E. Hornschemeier·P. Broos·L. Townsley·D. P. Schneider

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Abstract

We briefly report here on our ongoing X-ray spectroscopy and variability analyses of 136 faint X-ray sources discovered in the 2 Ms Chandra Deep Field North observations spanning 1.4x10-15 to 2x10-13 ergs s-1 cm-2. Most sources are adequatley fitted with a simple intrinsic absorption plus power-law model, although the resulting photon index is much lower than the canonical average unabsorbed spectral slope found locally (suggesting additional spectral complexity). Among the 136 sources, 7% show significant Fe (Ka) emission features, with equivalent widths in the range 0.1-1.3 keV. Two of these emission-line sources appear to be Compton thick. For the subset of sources with redshifts, we also find that fewer than 10% are likely to be Compton thick. Finally, ~60% of the sample show signs of long-term variability. This fraction climbs to ~90% for the bright sources (>500 cnts) or BLAGN.

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BibTeX RIS

F. E. Bauer, C. Vignali, D. M. Alexander, W. N. Brandt, G. P. Garmire, A. E. Hornschemeier, P. Broos, L. Townsley, D. P. Schneider. 2002-10-14. The AGN Source Population in the Chandra Deep Field-North Survey: Constraints from X-ray Spectroscopy and Variability. https://doi.org/10.1002/asna.200310074

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