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Title: Dynamical behavior of X-ray spectra from Markarian 766

Mrk 766, a bright narrow-line Seyfert 1, has been observed eight times by the XMM-Newton satellite. We carried out the analysis of the composite data from all of these observations together by applying a dynamical method. Through this analysis, we noted a longer timescale variability in addition to rapid short-time variability. This longer term variability is manifested by the presence of two distinct branches in flux-flux plots. Moreover, the data show the presence of absorbing material whose average thickness decreases gradually from ∼2 × 10{sup 23} cm{sup –2} during the dim state to ∼10{sup 22} cm{sup –2} as the source brightens to brighter states. To explain this longer timescale behavior and others already found self-consistently, we offer a promising model. In this model, the source is dim when a small emission region is covered by a small, denser portion of a partial-covering cloud; the source brightens as it becomes larger and covered predominantly by a less dense, larger region of the covering cloud. The short rapid variability, in contrast, is consistent with the highly variable power-law component from the coronal primary emission region, which is superimposed onto a less variable, ionized relativistic reflection component. Last, a possible presence of somemore » unique soft flares is suggested. Unlike many other flares seen in the light curves, these flares occur only in the 0.3-2.0 keV soft band. These soft flares may be attributed to 'hot spots' on the accretion disk.« less
Authors:
;  [1] ; ;  [2] ;  [3] ;  [4]
  1. Department of Physics, Montana State University, Bozeman, MT 59717 (United States)
  2. Department of Physics, Nagoya University, Furo-co, Chikusa-Ku, Nagoya 464-8602 (Japan)
  3. Department of Physics and Astronomy, Aichi University of Education, Kariya, Aichi 448-8543 (Japan)
  4. Department of Natural and Physical Sciences, Tomakomai National College of Technology, Tomakomai 0591-1257 (Japan)
Publication Date:
OSTI Identifier:
22348329
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 780; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; EMISSION; REFLECTION; RELATIVISTIC RANGE; SATELLITES; THICKNESS; VISIBLE RADIATION; X-RAY GALAXIES; X-RAY SPECTRA