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We investigate what powers hyperluminous infrared galaxies (HyLIRGs; $$L_{\rm IR, 8-1000\,\mu m}>10^{13}$$  L⊙) at z ∼ 1–2, by examining the behaviour of the infrared luminosity function of active galactic nuclei (AGN) in relation to the infrared galaxy luminosity function. The former corresponds to emission from AGN-heated dust only, whereas the latter includes emission from dust heated by stars and AGN. Our results show that the two luminosity functions are substantially different below 1013 L⊙ but converge in the HyLIRG regime. We find that the fraction of AGN-dominated sources increases with the total infrared luminosity and at $$L_{\rm IR}>10^{13.5}\, \rm L_{\odot }$$ AGN can account for the entire infrared emission. We conclude that the bright end of the 1 < $$z$$ < 2 infrared galaxy luminosity function is shaped by AGN rather than star-forming galaxies. [ABSTRACT FROM AUTHOR]

We correlate the positions of radio galaxies in the FIRST survey with the cosmic microwave background lensing convergence estimated from the Atacama Cosmology Telescope over 470 deg² to determine the bias of these galaxies. We remove optically cross-matched sources below redshift z = 0.2 to preferentially select active galactic nuclei (AGN). We measure the angular cross-power spectrum C1kg l at 4.4σ significance in the multipole range 100 < l < 3000, corresponding to physical scales within ≈2-60 Mpc at an effective redshift zeff = 1.5. Modelling the AGN population with a redshift-dependent bias, the cross-spectrum is well fitted by the Planck best-fitting Λ cold dark matter cosmological model. Fixing the cosmology and assumed redshift distribution of sources, we fit for the overall bias model normalization, finding b(zeff) = 3.5 ± 0.8 for the full galaxy sample and b(zeff) = 4.0 ± 1.1(3.0 ± 1.1) for sources brighter (fainter) than 2.5 mJy. This measurement characterizes the typical halo mass of radio-loud AGN: we find log(Mhalo/M⊙) = 13.6+0.3-0.4. [ABSTRACT FROM AUTHOR]