Presentation #106.39 in the session “AGN (Poster)”.
The X-ray spectra of most active galactic nuclei (AGNs) exhibit a ‘soft excess’ at energies less than ~2 keV. This emission sits above what would be expected from the hard X-ray power-law, but its origin is not well understood. Two recent models for the soft excess are relativistically blurred reflection from the inner accretion disc, or Comptonization in a warm corona located near the surface of the accretion flow. However, it is likely that both situations may occur at the same time, and the soft excess may be formed from the combination of both reflection and warm Comptonization. Here, we present the results of a new 2D, phenomenological X-ray spectral model of AGNs, that self-consistently predicts the reflection and emission spectra from the inner 400 rg of an AGN accretion disk. The model includes the effects of a warm corona, light-bending and relativistic blurring, and is available as XSPEC-friendly grids for use with XMM-Newton and NuSTAR data. We present an overview of the model and results from fitting the grids to multi-epoch observations of 2 AGNs. Our results show that the soft excess can be explained as emission from both reflection and a warm corona, and that the warm corona heating power varies with X-ray flux.