98 08 18 3 v 1 1 8 A ug 1 99 8 SIGNATURES OF RESONANT ABSORPTION IN X - RAY SPECTRA OF TYPE 1 AGN
نویسندگان
چکیده
We present photoionization models accounting for both photoelectric and resonant absorption. We demonstrate that resonance absorption lines are detectable even in moderate resolution X-ray spectra of type 1 AGN. The spectra transmitted by gas illuminated by the ionizing continua typical of flat X-ray spectrum, broad optical emission line type 1 AGN, and steep X-ray spectrum, narrow optical emission line type 1 AGN (NLSy1) are dramatically different. In particolar, we find that both the absorption features seen in many Seyfert 1 galaxies between 0.7 and 1 keV and in several NLSy1 between 1 and 2 keV can be explained by our model, without requiring relativistic outflowing velocities of the gas. 1 Introduction Soft X-ray spectra of X-ray flat, broad optical emission line type 1 AGN frequently show signatures of reprocessing by ionized matter along the line of sight (Reynolds,
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