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Quasi-Periodic Oscillation in Seyfert galaxies: Significance levels. The Case of Mrk 766

S. Benlloch·J. Wilms·R. Edelson·T. Yaqoob·R. Staubert
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Abstract

We discuss methods to compute significance levels for the existence of quasi-periodic oscillations (QPOs) in Active Galactic Nuclei (AGN) which take the red-noise character of the X-ray lightcurves of these objects into account. Applying epoch folding and periodogram analysis to the XMM-Newton observation of the Seyfert galaxy Mrk 766, a possible QPO at a timescale of 4200s has been reported. Our computation of the significance of this QPO, however, shows that the 4200s peak is not significant at the 95% level. We conclude that the 4200s feature is an artifact of the red-noise process and not the result of a physical process within the Active Galactic Nuclei.

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S. Benlloch, J. Wilms, R. Edelson, T. Yaqoob, R. Staubert. 2001-10-09. Quasi-Periodic Oscillation in Seyfert galaxies: Significance levels. The Case of Mrk 766. https://doi.org/10.1086/338252

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