The Seyfert Galaxy NGC 6814 -- a highly variable X-ray source
Astrophysics
2007-05-23 v1
Abstract
The Seyfert galaxy NGC 6814 is a highly variable X-ray source despite the fact that it has recently been shown not to be the source of periodic variability. The 1.5 year monitoring by ROSAT has revealed a long term downward trend of the X-ray flux and an episode of high and rapidly varying flux (e.g. by a factor of about 3 in 8 hours) during the October 1992 PSPC observation. Temporal analysis of this data using both Fourier and autoregressive techniques have shown that the variability timescales are larger than a few hundred seconds. The behavior at higher frequencies can be described by white noise.
Cite
@article{arxiv.astro-ph/9612176,
title = {The Seyfert Galaxy NGC 6814 -- a highly variable X-ray source},
author = {Michael Koenig and Susanne Friedrich and Ruediger Staubert and Jens Timmer},
journal= {arXiv preprint arXiv:astro-ph/9612176},
year = {2007}
}
Comments
5 pages, Latex, 6 PostScript figures, to be published in Astron. and Astrophys