Warm Absorbers in Seyfert 1 Galaxies
نویسنده
چکیده
X-ray spectroscopy of Seyfert 1 galaxies often reveal absorption edges resulting from photoionized gas along the line-of-sight to the central engine, the so-called warm absorber. I discuss how recent ASCA observations of warm absorber variability in MCG?6-30-15 can lead us to reject a one-zone model and, instead, have suggested a multi-zone warm absorber. The evidence for dust within the warm absorbers of MCG?6-30-15 and IRAS 13349+2438 is also addressed. These dusty warm absorbers reveal themselves by signiicantly reddening the optical ux without heavily absorbing the soft X-ray photons. Thermal emission from this warm/hot dust may be responsible for the infra-red bump commonly seen in the broad band spectrum of many Seyfert galaxies.
منابع مشابه
ar X iv : a st ro - p h / 97 04 13 1 v 1 1 4 A pr 1 99 7 Warm absorbers in Seyfert 1 galaxies
X-ray spectroscopy of Seyfert 1 galaxies often reveal absorption edges resulting from photoionized gas along the line-of-sight to the central engine, the so-called warm absorber. I discuss how recent ASCA observations of warm absorber variability in MCG−6-30-15 can lead us to reject a one-zone model and, instead, have suggested a multi-zone warm absorber. The evidence for dust within the warm a...
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