The Spin of the Supermassive Black Hole in NGC 3783

TL;DR

This study analyzes the supermassive black hole spin in NGC 3783 using Suzaku X-ray data, finding a high spin parameter and discussing implications for black hole growth and AGN populations.

Contribution

First measurement of black hole spin in NGC 3783 using relativistic reflection modeling with Suzaku data, providing insights into black hole spin distribution.

Findings

Black hole spin in NGC 3783 is greater than 0.88 at 99% confidence.

Relativistic reflection detected from the inner accretion disk.

Results suggest high spins may be common in local AGN.

Abstract

The Suzaku AGN Spin Survey is designed to determine the supermassive black hole spin in six nearby active galactic nuclei (AGN) via deep Suzaku stares, thereby giving us our first glimpse of the local black hole spin distribution. Here, we present an analysis of the first target to be studied under the auspices of this Key Project, the Seyfert galaxy NGC 3783. Despite complexity in the spectrum arising from a multi-component warm absorber, we detect and study relativistic reflection from the inner accretion disk. Assuming that the X-ray reflection is from the surface of a flat disk around a Kerr black hole, and that no X-ray reflection occurs within the general relativistic radius of marginal stability, we determine a lower limit on the black hole spin of a > 0.88 (99% confidence). We examine the robustness of this result to the assumption of the analysis, and present a brief discussion of spin-related selection biases that might affect flux-limited samples of AGN.