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arXiv · astro-ph/0510858

Discovery of a relativistic Fe line in PG 1425+267 with XMM--Newton and study of its short-timescale variability

Abstract

We report results from the XMM-Newton observation of the radio-loud quasar PG 1425+267 (z=0.366). The EPIC-pn data above 2 keV exhibit a double-peaked emission feature in the Fe K band. The higher energy peak is found at 6.4 keV and is consistent with being narrow, while the lower energy one is detected at 5.3 keV and is much broader than the detector resolution. We confirm the significance of the detection of the broad red part of the line via Montecarlo simulations. We explore two possible origins of the line profile i.e. a single relativistic iron line from the accretion disc, and the superposition of a narrow 6.4 keV line from distant material and a relativistic one. We find that a contribution from a distant reflector is not required by the data. We also perform a time-resolved analysis searching for short-timescale variability of the emission line. Results tentatively suggest that the line is indeed variable on short timescales and better quality data are needed to confirm it on more firm statistical grounds. We also detect clear signatures of a warm absorber in the soft X-ray energy band.

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G. Miniutti, A. C. Fabian. 2005-10-31. Discovery of a relativistic Fe line in PG 1425+267 with XMM--Newton and study of its short-timescale variability. https://doi.org/10.1111/j.1365-2966.2005.09805.x

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