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Title: ACTIVE GALACTIC NUCLEUS FEEDBACK WORKS BOTH WAYS

Simulations of galaxy growth need to invoke strong negative feedback from active galactic nuclei (AGNs) to suppress the formation of stars and thus prevent the over-production of very massive systems. While some observations provide evidence for such negative feedback, other studies find either no feedback or even positive feedback, with increased star formation associated with higher AGN luminosities. Here we report an analysis of several hundred AGNs and their host galaxies in the Chandra Deep Field South using X-ray and radio data for sample selection. Combined with archival far-infrared data as a reliable tracer of star formation activity in the AGN host galaxies, we find that AGNs with pronounced radio jets exhibit a much higher star formation rate (SFR) than the purely X-ray-selected ones, even at the same X-ray luminosities. This difference implies that positive AGN feedback plays an important role, too, and therefore has to be accounted for in all future simulation work. We interpret this to indicate that the enhanced SFR of radio-selected AGNs arises because of jet-induced star formation, as is suggested by the different jet powers among our AGN samples, while the suppressed SFR of X-ray selected AGN is caused by heating and photo-dissociation of molecularmore » gas by the hot AGN accretion disk.« less
Authors:
; ;  [1] ;  [2]
  1. Astronomical Institute of Ruhr-University Bochum, Universitaetsstrasse 150, D-44801 Bochum (Germany)
  2. CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia)
Publication Date:
OSTI Identifier:
22133918
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 774; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; DISSOCIATION; GALAXIES; GALAXY NUCLEI; HEATING; LUMINOSITY; SIMULATION; STARS; X RADIATION