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Date and Time of the Query: 2019-06-16 T11:41:46 PDT
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For refcode 1999ApJ...524..667T:
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1999ApJ...524..667T On X-Ray Variability in Seyfert Galaxies T. J. Turner, I. M. George, K. Nandra, and D. Turcan Received 1998 December 10; accepted 1999 June 8 ABSTRACT This paper presents a quantification of the X-ray variability amplitude for 79 ASCA observations of 36 Seyfert 1 galaxies. We find that consideration of sources with the narrowest permitted lines in the optical band introduces scatter into the established correlation between X-ray variability and nuclear luminosity. Consideration of the X-ray spectral index and variability properties together shows distinct groupings in parameter space for broad- and narrow-line Seyfert 1 galaxies, confirming previous studies. A strong correlation is found between hard X-ray variability and FWHM H{beta}. A range of nuclear mass and accretion rate across the Seyfert population can explain the differences observed in X-ray and optical properties. An attractive alternative model, which does not depend on any systematic difference in central mass, is that the circumnuclear gas of narrow-line Seyfert 1 galaxies is different from broad-line Seyfert 1 galaxies in temperature, optical depth, density, or geometry. Subject headings: galaxies: active-galaxies: nuclei-galaxies: Seyfert-X- rays: galaxies
Retrieve 36 NED objects in this reference.
Please click here for ADS abstract

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