The X-ray spectrum of NGC 7213 and the Seyfert-LINER connection

Abstract

We present an XMM-Newton observation of the Seyfert-LINER (low-ionization nuclear emission-line region) galaxy NGC 7213. The RGS soft X-ray spectrum is well fitted with a power law plus soft X-ray collisionally ionized thermal plasma (kT = 0.18-0.01+0.03 keV). We confirm the presence of Fe I, Fe XXV and Fe XXVI Kα emission in the EPIC spectrum and set tighter constraints on their equivalent widths of 82-13+10, 24-11+9 and 24-13+10 eV, respectively. We compare the observed properties together with the inferred mass accretion rate of NGC 7213 with those of other Seyfert and LINER galaxies. We find that NGC 7213 has intermediate X-ray spectral properties lying between those of the weak active galactic nucleus found in the LINER M81 and higher-luminosity Seyfert galaxies. There appears to be a continuous sequence of X-ray properties from the Galactic Centre through LINER galaxies to Seyferts, probably determined by the amount of material available for accretion in the central regions.