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An XMM-Newton observation of the Seyfert 1 galaxy 1H 0419-577 in an extreme low state

K. A. Pounds·J. N. Reeves·K. L. Page·P. T. O'Brien
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Abstract

Previous observations of the luminous Seyfert 1 galaxy 1H 0419-577 have found its X-ray spectrum to range from that of a typical Seyfert 1 with 2-10 keV power law index Gamma ~ 1.9 to a much flatter power law of Gamma ~ 1.5 or less. We report here a new XMM-Newton observation which allows the low state spectrum to be studied in much greater detail than hitherto. We find a very hard spectrum (Gamma ~ 1.0), which exhibits broad features that can be modelled with the addition of an extreme relativistic Fe K emission line or with partial covering of the underlying continuum by a substantial column density of near-neutral gas. Both the EPIC and RGS data show evidence for strong line emission of OVII and OVIII requiring an extended region of low density photoionised gas in 1H 0419-577. Comparison with an earlier XMM-Newton observation when 1H 0419-577 was 'X-ray bright' indicates the dominant spectral variability occurs via a steep power law component.

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K. A. Pounds, J. N. Reeves, K. L. Page, P. T. O'Brien. 2004-01-05. An XMM-Newton observation of the Seyfert 1 galaxy 1H 0419-577 in an extreme low state. https://doi.org/10.1086/382678

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