Bibcode
Coffey, D.; Longinotti, A.; Rodriguez-Ardila, A.; Guainazzi, M.; Miniutti, G.; Bianchi, S.; de la Calle, I.; Piconcelli, E.; Ballo, L.; Linares, M.
Referencia bibliográfica
The X-ray Universe 2014, edited by Jan-Uwe Ness. Online at http://xmm.esac.esa.int/external/xmm_science/workshops/2014symposium/, id.50
Fecha de publicación:
7
2014
Número de citas
0
Número de citas referidas
0
Descripción
In this work, the analysis of multi-epoch (1995-2010) X-ray observations
of the Seyfert 1 galaxy H0557-385 is presented. The wealth of data
presented in this analysis show that the source exhibits dramatic
spectral variability from a typical unabsorbed Seyfert 1 type spectrum
to a Compton-thin absorbed state on time scales of ˜ 5 years. This
extreme change in spectral shape can be attributed to variations in the
column density and covering fraction of a neutral absorbing medium
attenuating emission from the central continuum source. Evidence for
both Compton reflection and warm absorption have also been detected in
the spectra. Optical spectroscopy observations concurrent with a 2010
XMM-Newton observation campaign have detected the presence of broad
optical emission lines during an X-ray absorption event. From the
analysis of both X-ray and optical spectroscopic data, it has been
inferred that the X-ray spectral variability is a result of obscuration
of the central emission region by a clumpy absorber, located outside the
broad line region, which covers ≥ 80 per cent of the source with an
average column density of N_{H} ˜ 7×10^{23} cm^{-2}.