Predictions for deep galaxy surveys with JWST from ΛCDM

Cowley, W.I.; Baugh, C.M.; Cole, S.; Frenk, C.S.; Lacey, C.G.

Abstract

We present predictions for the outcome of deep galaxy surveys with the James Webb Space Telescope (JWST) obtained from a physical model of galaxy formation in Λ cold dark matter. We use the latest version of the GALFORM model, embedded within a new (800 Mpc)3 dark matter only simulation with a halo mass resolution of Mhalo > 2 × 109h−1 M⊙. For computing full UV-to-mm galaxy spectral energy distributions, including the absorption and emission of radiation by dust, we use the spectrophotometric radiative transfer code GRASIL. The model is calibrated to reproduce a broad range of observational data at z ≲ 6, and we show here that it can also predict evolution of the rest-frame far-UV luminosity function for 7 ≲ z ≲ 10 which is in good agreement with observations. We make predictions for the evolution of the luminosity function from z = 16 to z = 0 in all broad-band filters on the Near InfraRed Camera (NIRCam) and Mid InfraRed Instrument (MIRI) on JWST and present the resulting galaxy number counts and redshift distributions. Our fiducial model predicts that ∼1 galaxy per field of view will be observable at z ∼ 11 for a 104 s exposure with NIRCam. A variant model, which produces a higher redshift of reionization in better agreement with Planck data, predicts number densities of observable galaxies ∼5 × greater at this redshift. Similar observations with MIRI are predicted not to detect any galaxies at z ≳ 6. We also make predictions for the effect of different exposure times on the redshift distributions of galaxies observable with JWST, and for the angular sizes of galaxies in JWST bands.

Citation

Cowley, W., Baugh, C., Cole, S., Frenk, C., & Lacey, C. (2018). Predictions for deep galaxy surveys with JWST from ΛCDM. Monthly Notices of the Royal Astronomical Society, 474(2), 2352-2372. https://doi.org/10.1093/mnras/stx2897

• Journal Article Type: Article
• Acceptance Date: Nov 2, 2017
• Online Publication Date: Nov 13, 2017
• Publication Date: Feb 21, 2018
• Deposit Date: Jan 15, 2018
• Publicly Available Date: Jan 16, 2018
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 474
• Issue: 2
• Pages: 2352-2372
• DOI: https://doi.org/10.1093/mnras/stx2897
• Public URL: https://durham-repository.worktribe.com/output/1340930