No Clear Submillimeter Signature Of Suppressed Star Formation Among X-Ray Luminous Active Galactic Nuclei
Publication date: 02 November 2012
Authors: Harrison, C., et al.
Journal: The Astrophysical Journal Letters
Copyright: IOP Publishing
Many theoretical models require powerful active galactic nuclei (AGNs) to suppress star formation in distant galaxies and reproduce the observed properties of today's massive galaxies. A recent study based on Herschel-SPIRE submillimeter observations claimed to provide direct support for this picture, reporting a significant decrease in the mean star formation rates (SFRs) of the most luminous AGNs (Lx >1044 erg s-1) at z ~ 1-3 in the Chandra Deep Field-North (CDF-N). In this Letter, we extend these results using Herschel-SPIRE 250 micron data in the COSMOS and Chandra Deep Field-South fields to achieve an order-of-magnitude improvement in the number of sources at Lx >1044 erg s-1. On the basis of our analysis, we find no strong evidence for suppressed star formation in Lx >1044 erg s-1 AGNs at z ~ 1-3. The mean SFRs of the AGNs are constant over the broad X-ray luminosity range of Lx 1043-1045 erg s-1 (with mean SFRs consistent with typical star-forming galaxies at z ~ 2; SFRs ~ 100-200 M_Sun