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X-ray emitting AGN unveiled by the Chandra Multiwavelength Project

John D. Silverman·Paul J. Green·Thomas L. Aldcroft·Dong-Woo Kim·Wayne Barkhouse·Robert A. Cameron·Belinda J. Wilkes
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Abstract

We present an X-ray and optical analysis of a 2-8 keV flux limited (fx > 10e-14 erg s^-1 cm^-2) sample of 126 AGN detected in 16 Chandra fields. This work represents a small though significant subset of the Chandra Multiwavelength Project (ChaMP). We have chosen this limiting flux to have a reasonable degree of completeness (50%) in our optical spectroscopic identifications. The optical counterparts of these AGN are characterized as either broad emission line AGN (BLAGN; 67%), narrow emission line galaxies (NELG; 22%) or absorption line galaxies (ALG; 11%) without any evidence of an AGN signature. Based on their X-ray luminosity and spectral properties, we show that NELG and ALG are primarily the hosts of obscured AGN with an intrinsic absorbing column in the range of 10^21.5<NH<10^23.3 cm^-2. While most of the BLAGN are unobscured, there are a few with substantial absorption. X-ray surveys such as the ChaMP nicely complement the SDSS to determine the demographics of the AGN population.

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John D. Silverman, Paul J. Green, Thomas L. Aldcroft, Dong-Woo Kim, Wayne Barkhouse, Robert A. Cameron, Belinda J. Wilkes. 2003-10-31. X-ray emitting AGN unveiled by the Chandra Multiwavelength Project. https://arxiv.org/abs/astro-ph/0310907

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