The origin of the infrared emission in radio galaxies II: analysis of mid- to far-infrared Spitzer observations of the 2Jy sample

Understand

We present an analysis of deep mid- to far-infrared (MFIR) Spitzer photometric observations of the southern 2Jy sample of powerful radio sources (0.05 < z < 0.7), conducting a statistical investigation of the links between radio jet, AGN, starburst activity and MFIR properties.

• This is part of an ongoing extensive study of powerful radio galaxies that benefits from both complete optical emission line information and a uniquely high detection rate in the far-infrared (far-IR).
• We find tight correlations between the MFIR and [OIII] emission luminosities, which are significantly better than those between MFIR and extended radio luminosities, or between radio and [OIII] luminosities.
• Since [OIII] is a known indicator of intrinsic AGN power, these correlations confirm AGN illumination of the circum-nuclear dust as the primary heating mechanism for the dust producing thermal MFIR emission at both 24 and 70 microns.