X-ray spectral analysis of the low-luminosity active galactic nucleus NGC 7213 using long XMM-Newton observations

Abstract

We present the X-ray spectral results from the longest X-ray Multi-mirror Mission-Newton observation, 133 ks, of the low-luminosity active galactic nucleus NGC 7213. The hardnessratio analysis of the X-ray light curves discloses a rather constant X-ray spectral shape, at least for the observed exposure time, enabling us to perform X-ray spectral studies using the total observed spectrum. Apart from a neutral Fe Kα emission line, we also detect narrow emission lines from the ionized iron species, Fe XXV and Fe XXVI. Our analysis suggests that the neutral Fe Kα originates from a Compton-thin reflector, while the gas responsible for the high-ionization lines is collisionally excited. The overall spectrum, in the 0.3-10 keV energy band, registered by the European Photon Imaging Camera can be modelled by a power-law component (with a slope of g{cyrillic} ≃ 1.9) plus two thermal components at 0.36 and 8.84 keV. The low-energy thermal component is entirely consistent with the X-ray spectral data obtained by the Reflection Grating Spectrometer between 0.35-1.8 keV. © 2013 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.