Coronal-Line Forest AGN: the best view of the inner edge of the AGN torus?

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We introduce Coronal-Line Forest Active Galactic Nuclei (CLiF AGN), AGN which have a rich spectrum of forbidden high-ionization lines (FHILs, e.g. [FeVII], [FeX] and [NeV]), as well as relatively strong narrow (300 km s⁻¹) Hα emission when compared to the other Balmer transition lines. We find that the kinematics of the CLiF emitting region are similar to those of the forbidden low-ionization emission-line (FLIL) region. We compare emission line strengths of both FHILs and FLILs to CLOUDY photoionization results and find that the CLiF emitting region has higher densities (10⁴.⁵ < nₕ < 10⁷.⁵ cm⁻³) when compared to the FLIL emitting region (10³.⁰ < nₕ < 10⁴.⁵ cm⁻³). We use the photoionization results to calculate the CLiF regions radial distances (0.04 < RCLiF < 32.5 pc) and find that they are comparable to the dust grain sublimation distances (0.10 < RSUB < 4.3 pc). As a result we suggest that the inner torus wall is the most likely location of the CLiF region, and the unusual strength of the FHILs is due to a specific viewing angle giving a maximal view of the far wall of the torus without the continuum being revealed.