ar X iv : a st ro - p h / 98 08 20 5 v 1 1 9 A ug 1 99 8 Properties of warm absorbers in active galaxies
نویسنده
چکیده
We present a study of the nature of warm absorbers on the basis of ROSAT X-ray observations and photoionization calculations carried out with the code Cloudy. We focus on ‘non-standard’ warm absorbers: (i) the proposed dusty warm absorbers in IRAS 13349+2438 and IRAS 17020+4544, and possibly in 4C+74.26, (ii) we explore several scenarios to account for the recently observed peculiar absorption features around ∼1.1 keV on the basis of detailed photoionization models, and apply these to PG1404+226.
منابع مشابه
ar X iv : a st ro - p h / 98 08 21 9 v 1 2 0 A ug 1 99 8 Sgr A ∗ : A supermassive black hole or a spatially extended object ?
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