The BlueTides Mock Image Catalogue: Simulated observations of high-redshift galaxies and predictions for JWST imaging surveys

TL;DR

This paper creates a detailed simulated catalogue of high-redshift galaxies and assesses the detection capabilities of current and upcoming space telescopes, especially JWST, for these distant objects.

Contribution

It introduces a comprehensive mock image catalogue of high-redshift galaxies and predicts their detectability with various telescopes and surveys, aiding future observational planning.

Findings

JWST will detect galaxies 2.5 magnitudes fainter than VISTA and Subaru.

NIRCam F356W and F277W filters will reach 95% completeness at m=27.4 in 10ks.

Upcoming JWST surveys like COSMOS-Web will find around 1000 galaxies at z=6.5-7.5.

Abstract

We present a mock image catalogue of ~100,000 MUV=-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 (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% completeness limit at least 2.5 magnitudes fainter than VISTA and Subaru, 1.1 magnitudes fainter than Hubble, and 0.9 magnitudes 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% completeness at m=27.4 mag in 10ks 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 MUV<-20.1 mag galaxies at 6.5<z<7.5, by virtue of its large survey area. JADES-Medium will detect almost 100% of MUV<-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.