Extreme warm absorber variability in the Seyfert galaxy Mrk 704

@article{Matt2011ExtremeWA,
  title={Extreme warm absorber variability in the Seyfert galaxy Mrk 704},
  author={Giorgio Matt and Stefano Bianchi and Matteo Guainazzi and A. L. Longinotti and Mauro Dadina and Vladim{\'i}r Karas and Giuseppe Malaguti and Giovanni Miniutti and P.-O. Petrucci and Enrico Piconcelli and Gabriele Ponti},
  journal={Astronomy and Astrophysics},
  year={2011},
  volume={533}
}
Context. In about half of Seyfert galaxies, the X-ray emission is absorbed by an optically thin, ionized medium, the so-called “Warm Absorber”, whose origin and location is still a matter of debate. Aims. The aims of this paper is to put more constraints on the warm absorber by studying its variability. Methods. We analyzed the X-ray spectra of a Seyfert 1 galaxy, Mrk 704, which was observed twice, three years apart, by XMMNewton. Results. The spectra were well fitted with a two zones absorber… 
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