An X-ray timing analysis of narrow-line and broad-line Seyfert 1 galaxies with Suzaku

Abstract

The Suzaku X-ray satellite has been decommissioned since 2015, leaving us with a known catalogue of observed active galactic nuclei (AGN). This work provides a timing analysis of all broad-line and narrow-line Seyfert 1 AGN observed by the XIS instrument aboard Suzaku, sensitive over ∼ 0.5 – 10 keV. Extreme variability is a ubiquitous trait among AGN, varying in brightness on characteristic timescales of hours up to weeks. The changing brightness is associated with physical components of the AGN, leading to well established relations between variability and physical parameters, such as the black hole mass (M_BH). We analyze the 0.5 – 10 keV structure functions for the sample, yielding a mean power law index of 1.00 ± 0.09, and a mean break of 0.22 ± 0.04 days. Furthermore, we calculate the excess variance on 60 ks, 100ks, and 150 ks durations and reproduce the M_BH vs. σ²_rms relation at each timescale. We also identify strong correlations between the soft excess and σ²_rms,0.5-2keV at each timescale, as well as weaker correlations between τ_char and β.