2008/10/02 by E. Jimenez-Bailon, E. Jiménez-Bailón, Y. Krongold +6
Physics and Astronomy · #Absorption (acoustics) #Absorption spectroscopy #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Emission spectrum #Galaxies: Formation, Evolution, Phenomena #Galaxy #Ionization #K-line #Line (geometry) #Spectral line #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2008.13976.x
11 pages, accepted in MNRAS
arxiv created 2008/10/02 · openalex publication_date 2008/11/11 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report on the X-ray observation of the Seyfert 1 galaxy ESO 323-G077 performed with XMM-Newton. The EPIC spectra show a complex spectrum with conspicuous absorption and emission features. The continuum emission can be modelled with a power law with an index of 1.99 +/- 0.02 in the whole XMM-Newton energy band, marginally consistent with typical values of type I objects. An absorption component with an uncommonly high equivalent hydrogen column (n(H) = 5.82(-0.11)(+ 0.12) x 10(22) cm(-2)) is affecting the soft part of the spectrum. Additionally, two warm absorption components are also present in the spectrum. The lower ionized one, mainly imprinting the soft band of the spectrum, has an ionization parameter of log U = 2.14(-0.07)(+ 0.06) and an outflowing velocity of v = 3200(-200)(+600) km s(-1). Two absorption lines located at similar to 6.7 and similar to 7.0 keV can be modelled with the highly ionized absorber. The ionization parameter and outflowing velocity of the gas measured are log U = 3.26(-0.15)(+0.19) and v = 1700(-400)(+600) km s(-1), respectively. Four emission lines were also detected in the soft energy band. The most likely explanation for these emission lines is that they are associated with an outflowing gas with a velocity of similar to 2000 km s(-1). The data suggest that the same gas which is causing the absorption could also being responsible of these emission features. Finally, the XMM-Newton spectrum shows the presence of a relativistic iron emission line likely originated in the accretion disc of a Kerr black hole with an inclination of similar to 25 degrees. We propose a model to explain the observed X-ray properties which invokes the presence of a two-phase outflow with cone-like structure and a velocity of the order of 2000-4000 km s(-1). The inner layer of the cone would be less ionized, or even neutral, than the outer layer. The inclination angle of the source would be lower than the opening angle of the outflowing cone.