Probing the unified model in NGC 7314

TL;DR

This study analyzes X-ray spectra from multiple observatories to understand the complex absorption features in NGC 7314, revealing multiple ionization phases and supporting a clumpy torus model in active galactic nuclei.

Contribution

It provides a multi-instrument analysis of the absorption features in NGC 7314, identifying distinct ionization phases and proposing a geometric model consistent with the unified AGN framework.

Findings

Detection of three ionization phases in the ionized gas.

Evidence of neutral and ionized absorption varying across observations.

Identification of Fe Kalpha, Fe XXVI, and Fe Kbeta emission lines.

Abstract

We present a study of the complex absorbed X-ray spectrum of the Narrow Line Seyfert 1 galaxy NGC 7314. We collected available public X-ray data from the archives of XMM-Newton, Suzaku, and ASCA. The spectra were analyzed using the fitting package SPEX. We find evidence of intrinsic neutral and ionized absorption in the XMM-Newton EPIC-pn spectrum. The ionized gas presents three significantly distinct ionization phases, although its kinematic properties could not be disentangled. At least two of these phases are also detected in the RGS spectrum, although with less significance due to the low statistics. The ASCA and Suzaku spectra show larger neutral absorption but no ionized gas signatures. The Fe Kalpha emission line is detected in all the observations and, additionally, Fe XXVI in the EPIC-pn spectrum, and Fe Kbeta in the Suzaku XIS spectrum. Using this observational evidence we construct a consistent picture of the geometry of the system in the context of the unified model of active galactic nuclei. The different observational properties are thus interpreted as clouds of neutral gas moving across our line of sight, which would be grazing a clumpy dusty torus.