Abstract. We study the narrow-line region (NLR) of six Seyfert-1 and six Seyfert-2 galaxies by means of spatially resolved optical spectroscopy and photoionization modelling. From spatially resolved spectral diagnostics, we find a transition between the AGN-excited NLR and the surrounding star-forming regions, allowing us to determine the NLR size independent of stellar contamination. CLOUDY photoionization models show that the observed transition represents a true difference in ionization source and cannot be explained by variations of physical parameters. The electron density and ionization parameter decrease with radius indicating that the NLR is photoionized by the central source only. The velocity field suggests a disky NLR gas distribution. The Narrow-Line Region in Active Galaxies The narrow-line region (NLR) in active galactic nuclei (AGNs) is ideally suited to study the central region through its various emission lines. It has the great advantage over the broad-line region (BLR) to be spatially resolvable, at least for nearby AGNs. Since the NLR is affected by various parameters such as th
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