2016MNRAS.461.1621C

We present predictions for the clustering of galaxies selected by their emission at far-infrared (FIR) and sub-millimetre wavelengths. This includes the first predictions for the effect of clustering biases induced by the coarse angular resolution of single-dish telescopes at these wavelengths. We combine a new version of the galform model of galaxy formation with a self-consistent model for calculating the absorption and re-emission of radiation by interstellar dust. Model galaxies selected at 850µm reside in dark matter haloes of mass M_halo ∼ 10^11.5-10¹²h^–1 M_☉, independent of redshift (for 0.2 <= z <= 4) or flux (for 0.25 <= S_850 µm_ <= 4 mJy). At z ∼ 2.5, the brightest galaxies (S_850 µm_ > 4 mJy) exhibit a correlation length of r_{0}=5.5{-0.5}^{+0.3}h-1^ Mpc, consistent with observations. We show that these galaxies have descendants with stellar masses M_* ∼ 10¹¹h^–1 M_☉ occupying haloes spanning a broad range in mass M_halo ∼ 10¹²-10¹⁴h^–1 M_☉. The FIR emissivity at shorter wavelengths (250, 350 and 500 µm) is also dominated by galaxies in the halo mass range M_halo ∼ 10^11.5-10¹²h^–1 M_☉, again independent of redshift (for 0.5 <= z <= 5). We compare our predictions for the angular power spectrum of cosmic infrared background anisotropies at these wavelengths with observations, finding agreement to within a factor of ∼2 over all scales and wavelengths, an improvement over earlier versions of the model. Simulating images at 850 µm, we show that confusion effects boost the measured angular correlation function on all scales by a factor of ∼4. This has important consequences, potentially leading to inferred halo masses being overestimated by an order of magnitude.