A global view of reverberation in bare Seyferts
Abstract
In recent years, X-ray reverberation has opened a new way to investigate the inner accretion flow around supermassive black holes. XMM-Newton and NuSTAR observations of the high-frequency variability have shown that the soft excess, broad iron K line and even the Compton hump lag behind the continuum emission, suggesting light travel distances of a few gravitational radii. In addition to high-frequency reverberation, there are also featureless low-frequency lags that have been observed commonly in AGN and black hole binaries for many years, and are often attributed the continuum emission. Through observations of individual sources, we are beginning to understand more about the low- and high-frequency X-ray lags, however, a systematic search is required to obtain a global view of reverberation in bare Seyferts. In particular, we need to understand how common iron K lags are, how the lags depend on the geometry of the accretion flow, and the effect of low-frequency absorption variability. In this talk, I will review some of the most recent XMM-Newton and NuSTAR observational results, and will also present results on a global look at reverberation in bare Seyferts.
- Publication:
-
The Extremes of Black Hole Accretion
- Pub Date:
- July 2015
- Bibcode:
- 2015ebha.confE..40K