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arXiv · 0708.0751

On the relativistic iron line and soft excess in the Seyfert 1 galaxy Markarian 335

Paul M. O'Neill·Kirpal Nandra·Massimo Cappi·Anna Lia Longinotti·Stuart A. Sim
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Abstract

We report on a 133 ks XMM-Newton observation of the Seyfert 1 galaxy Markarian 335. The 0.4-12 keV spectrum contains an underlying power law continuum, a soft excess below 2 keV, and a double-peaked iron emission feature in the 6-7 keV range. We investigate the possibility that the double-peaked emission might represent the characteristic signature of the accretion disc. Detailed investigations show that a moderately broad, accretion disc line is most likely present, but that the peaks may be owing to narrower components from more distant material. The peaks at 6.4 and 7 keV can be identified, respectively, with the molecular torus in active galactic nucleus unification schemes, and very highly ionized, optically thin gas filling the torus. The X-ray variability spectra on both long (~100 ks) and short (~1 ks) timescales disfavour the recent suggestion that the soft excess is an artifact of variable, moderately ionized absorption.

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Paul M. O'Neill, Kirpal Nandra, Massimo Cappi, Anna Lia Longinotti, Stuart A. Sim. 2007-08-06. On the relativistic iron line and soft excess in the Seyfert 1 galaxy Markarian 335. https://doi.org/10.1111/j.1745-3933.2007.00376.x

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