The infrared emission from the narrow line region

¹ Max Planck Institute for Astrophysics, Karl-Schwarzschild str. 1, 85741 Garching, Germany e-mail: brent@mpa-garching.mpg.de
² Research School of Astronomy & Astrophysics, The Australian National University, Cotter Road, Weston Creek, ACT 2611, Australia

Received: 27 February 2006
Accepted: 26 July 2006

Abstract

We present models for the mid- and far- infrared emission from the Narrow Line Region (NLR) of Active Galactic Nuclei (AGN). Using the MAPPINGS iii code we explore the effect of typical NLR  parameters on the spectral characteristics of the IR emission. These include useful IR emission line ratio diagnostic diagrams for the determination of these parameters, as well as Star formation-AGN mixing diagnostics. We also examine emission line to continuum correlations which would assist in separating the IR emission arising from the NLR from that coming from the inner torus. We find for AGN like NGC 1068 and NGC 4151 that the NLR only contributes ~10% to the total IRAS 25 mum flux, and that other components such as a dusty torus are necessary to explain the total AGN IR emission.