The Black Hole Spin and Soft X-ray Excess of the Luminous Seyfert Galaxy Fairall 9

TL;DR

This study analyzes X-ray spectra of Fairall 9 to investigate black hole spin, accretion disk inclination, and soft X-ray excess, revealing complex reflection features and variable soft excess components.

Contribution

It provides the first multi-epoch analysis combining XMM-Newton and Suzaku data to constrain the black hole spin and accretion disk properties in Fairall 9.

Findings

Robust evidence for a broad iron line from the innermost accretion disk.

Detection of a soft X-ray excess that varies across epochs.

Identification of additional soft components possibly due to ionized reflection or new continuum.

Abstract

We present an analysis of all XMM-Newton and Suzaku X-ray spectra of the nearby luminous Seyfert galaxy Fairall 9. Confirming previous analyses, we find robust evidence for a broad iron line associated with X-ray reflection from the innermost accretion disk. By fitting a spectral model that includes a relativistically ionized reflection component, we examine the constraints on the inclination of the inner accretion disk and the black hole spin, and the complications introduced by the presence of a photoionized emission line system. Employing multi-epoch fitting, we attempt to obtain robust and concordant measures of the accretion disk parameters. We also clearly see a soft X-ray excess in Fairall 9. During certain epochs, the soft excess can be described with same disk reflection component that produces the iron line. However, there are epochs where an additional soft component is required. This can be attributed to either an additional highly-ionized, strongly blurred disk reflection component, or a new X-ray continuum component.