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The X-ray variability properties of PG quasars: XMM-Newton results

M. Guainazzi·E. Jimenez-Bailon·E. Piconcelli
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Abstract

This paper presents preliminary results of a systematic study on the X-ray spectral variability of PG quasars with XMM-Newton. We concentrate on those objects, whose X-ray spectra are well fit in the framework of the ``double Comptonization'' model. On short (<1000 seconds) timescales, variability between the soft (E<2 keV) and the hard (E>2 keV) bands is uncorrelated. In the two objects, for which observations at different epochs are available, spectral variability in the soft X-ray regime is unveiled. Its timescale is constrained in the range between ~1 week and ~1 year.

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M. Guainazzi, E. Jimenez-Bailon, E. Piconcelli. 2004-09-17. The X-ray variability properties of PG quasars: XMM-Newton results. https://arxiv.org/abs/astro-ph/0409438

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