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Record 1 of 11685
X-ray bumps, iron K-alpha lines, and X-ray suppression by obscuring tori in Seyfert galaxies
External Online Source: doi:10.1086/187162
Author and Affiliation:
Krolik, Julian H.(Johns Hopkins University, Baltimore, MD, United States)
Madau, Piero(Space Telescope Science Institute, Baltimore, MD, United States)
Zycki, Piotr T.(Observatoire de Paris-Meudon, Meudon, France)
Abstract: We investigate the X-ray spectral properties of unobscured type 1 and obscured type 2 Seyferts as predicted by the unified Seyfert scheme. We consider the reprocessing of X-ray photons by photoelectric absorption, iron fluorescence, and Compton downscattering in the obscuring tori surrounding these active nuclei, and compute by Monte Carlo methods the reprocessed spectra as a function of the viewing angle. Depending on the optical depth and shape of the torus, and on the viewing angle, the X-ray flux can be suppressed by substantial factors when our line of sight is obscured. We show that an immediate consequence of the existence of an obscuring thick torus is the production in the spectra of type 1 Seyfert galaxies of a bump in the continuum above 10-20 keV and an Fe K-alpha line with significant equivalent width. In those type 2 Seyferts for which the hard X-ray spectrum has been substantially suppressed, the equivalent width of the Fe K-alpha line in the transmitted spectrum can be very large.
Publication Date: Jan 10, 1994
Document ID:
19950035373
(Acquired Dec 28, 1995)
Accession Number: 95A66972
Subject Category: ASTROPHYSICS
Document Type: Journal Article
Publication Information: Astrophysical Journal, Part 2 - Letters (ISSN 0004-637X); 420; 2; p. L57-L61
Publisher Information: United States
Contract/Grant/Task Num: NAGW-3129
Financial Sponsor: NASA; United States
Organization Source: NASA; Washington, DC, United States
Description: 5p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
NASA Terms: ACTIVE GALACTIC NUCLEI; COMPTON EFFECT; K LINES; PHOTOELECTRIC EMISSION; SEYFERT GALAXIES; X RAY SPECTRA; GINGA SATELLITE; LINE OF SIGHT; MONTE CARLO METHOD; OPACITY; OPTICAL THICKNESS; TORUSES
Imprint And Other Notes: Astrophysical Journal, Part 2 - Letters vol. 420, no. 2 p. L57-L61 January 10, 1994
Miscellaneous Notes: Research sponsored by the State Committee for Scientific Research
Availability Source: Other Sources
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