Dicken, D, Tadhunter, C, Axon, David, Robinson, A, Morganti, R and Kharb, P (2010) THE ORIGIN OF THE INFRARED EMISSION IN RADIO GALAXIES. III. ANALYSIS OF 3CRR OBJECTS. Astrophysical Journal, 722 (2). pp. 1333-1341. ISSN 0004-637X

Preview

PDF - Published Version Download (329kB) | Preview

Abstract

We present Spitzer photometric data for a complete sample of 19 low-redshift (z < 0.1) 3CRR radio galaxies as part of our efforts to understand the origin of the prodigious mid-to far-infrared (MFIR) emission from radio-loud active galactic nuclei (AGNs). Our results show a correlation between AGN power (indicated by [O III]lambda 5007 emission line luminosity) and 24 mu m luminosity. This result is consistent with the 24 mu m thermal emission originating from warm dust heated directly by AGN illumination. Applying the same correlation test for 70 mu m luminosity against [O III] luminosity we find this relation to suffer from increased scatter compared to that of 24 mu m. In line with our results for the higher-radio-frequency-selected 2 Jy sample, we are able to show that much of this increased scatter is due to heating by starbursts that boost the far-infrared emission at 70 mu m in a minority of objects (17%-35%). Overall this study supports previous work indicating AGN illumination as the dominant heating mechanism for MFIR emitting dust in the majority of low-to-intermediate redshift radio galaxies (0.03 < z < 0.7), with the advantage of strong statistical evidence. However, we find evidence that the low-redshift broad-line objects (z < 0.1) are distinct in terms of their positions on the MFIR versus [O III] correlations.

Item Type:	Article
Schools and Departments:	School of Mathematical and Physical Sciences > Physics and Astronomy
Depositing User:	David Axon
Date Deposited:	06 Feb 2012 20:32
Last Modified:	03 Jul 2019 01:15
URI:	http://sro.sussex.ac.uk/id/eprint/26453

View download statistics for this item

📧 Request an update