An X-ray spectral study of the origin of reflection features in bare Seyfert 1 galaxy ESO 511--G030

TL;DR

This study analyzes broadband X-ray and UV spectra of the Seyfert 1 galaxy ESO 511--G030, revealing details about its accretion disk, corona, and reflection features, and suggesting a rapidly spinning black hole with a compact corona.

Contribution

It provides a detailed spectral analysis of ESO 511--G030 using multi-epoch data, exploring models for the soft excess and reflection features, and inferring the black hole spin and corona properties.

Findings

Soft excess explained by thermal Comptonization or blurred reflection.

Black hole spin inferred to be greater than 0.78.

Accretion rate is sub-Eddington, around 0.004-0.008.

Abstract

The reprocessed X-ray emission from Active Galactic Nuclei (AGN) is an important diagnostic tool to study the dynamics and geometry of the matter surrounding the supermassive black holes (SMBHs). We present a broadband (optical-UV to hard X-ray) spectral study of the bare Seyfert 1 galaxy, ESO~511--G030, using multi-epoch Suzaku and XMM-Newton data from 2012 and 2007 respectively. The broadband spectra of ESO~511--G030 exhibit a UV bump, a prominent soft-excess below 2 keV, a relatively broad ($\sigma=0.08 - 0.14$ keV) Fe emission line at 6.4 keV and a weak Compton hump at E > 10 keV. The soft X-ray excess in ESO~511--G030 can be described either as the thermal Comptonization of disk seed photons by a warm ($0.40^{+0.02}_{-0.02}$ keV), optically thick ($\tau = 12.7^{+0.5}_{-0.4}$) and compact ($< 15 \rm r_{g}$) corona or as the blurred reflection from an untruncated and moderate to highly ionized accretion disk. However, for the blurred reflection, the model requires some extreme configuration of the disk and corona. Both these models prefer a rapidly spinning black hole ($a>0.78$) and a compact corona, indicating a relativistic origin of the broad Fe emission line. We found an inner disk temperature of $\sim 2-3$ eV that characterises the UV bump and the SMBH accretes at a sub-Eddington rate ($\lambda_{Edd} = 0.004-0.008$).