Identifying the subtle signatures of feedback from distant AGN using ALMA observations and the EAGLE hydrodynamical simulations
Artikel i vetenskaplig tidskrift, 2018

We present sensitive 870 μm continuum measurements from our ALMA programmes of 114 X-ray selected active galactic nuclei (AGN) in the Chandra Deep Field-South and Cosmic Evolution Survey fields. We use these observations in combination with data from Spitzer and Herschel to construct a sample of 86 X-ray selected AGN, 63 with ALMA constraints at Ζ = 1.5-3.2 with stellar mass > 2 × 10 10 M ⊙ . We constructed broad-band spectral energy distributions in the infrared band (8-1000 μm) and constrain star-formation rates (SFRs) uncontaminated by the AGN. Using a hierarchical Bayesian method that takes into account the information from upper limits, we fit SFR and specific SFR (sSFR) distributions. We explore these distributions as a function of both X-ray luminosity and stellar mass. We compare our measurements to two versions of the Evolution and Assembly of GaLaxies and their Environments (EAGLE) hydrodynamical simulations: the reference model withAGNfeedback and the model without AGN. We find good agreement between the observations and that predicted by the EAGLE reference model for the modes and widths of the sSFR distributions as a function of both X-ray luminosity and stellar mass; however, we found that the EAGLE model without AGN feedback predicts a significantly narrower width when compared to the data. Overall, from the combination of the observations with the model predictions, we conclude that (1) even with AGN feedback, we expect no strong relationship between the sSFR distribution parameters and instantaneous AGN luminosity and (2) a signature of AGN feedback is a broad distribution of sSFRs for all galaxies (not just those hosting an AGN) with stellar masses above ≈10 10 M ⊙ .


J. Scholtz

Durham University

D. M. Alexander

Durham University

C. M. Harrison

Durham University

European Southern Observatory (ESO)

D. J. Rosario

Durham University

S. McAlpine

Durham University

J. R. Mullaney

University of Sheffield

Flora Stanley

Durham University

Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik, Extragalaktisk astrofysik

J. M. Simpson

Academia Sinica

T. Theuns

Durham University

R. G. Bower

Durham University

R. C. Hickox

Dartmouth College

P. Santini

Osservatorio Astronomico di Roma

A.M. Swinbank

Durham University

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 475 1288-1305 stx3177


Subatomär fysik

Astronomi, astrofysik och kosmologi

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