2022MNRAS.516.1047M

We present a mock image catalogue of ∼100 000 M_UV ≃ -22.5 to -19.6 mag galaxies at z = 7-12 from the BLUETIDES cosmological simulation. We create mock images of each galaxy with the James Webb Space Telescope (JWST), Hubble, Roman, and Euclid Space Telescopes, as well as Subaru, and VISTA, with a range of near- and mid-infrared filters. We perform photometry on the mock images to estimate the success of these instruments for detecting high-z galaxies. We predict that JWST will have unprecedented power in detecting high-z galaxies, with a 95 per cent completeness limit at least 2.5 mag fainter than VISTA and Subaru, 1.1 mag fainter than Hubble, and 0.9 mag fainter than Roman, for the same wavelength and exposure time. Focusing on JWST, we consider a range of exposure times and filters, and find that the NIRCam F356W and F277W filters will detect the faintest galaxies, with 95 per cent completeness at m ≃ 27.4 mag in 10-ks exposures. We also predict the number of high-z galaxies that will be discovered by upcoming JWST imaging surveys. We predict that the COSMOS-Web survey will detect ∼1000 M_1500 Å_ < -20.1 mag galaxies at 6.5 < z < 7.5, by virtue of its large survey area. JADES-Medium will detect almost $100{{\ \rm per\ cent}}$ of M_1500 Å_ ≲ -20 mag galaxies at z < 8.5 due to its significant depth, however, with its smaller survey area it will detect only ∼100 of these galaxies at 6.5 < z < 7.5. Cosmic variance results in a large range in the number of predicted galaxies each survey will detect, which is more evident in smaller surveys such as CEERS and the PEARLS NEP and GOODS-S fields.