http://arxiv.org/abs/2109.14178
The James Webb Space Telescope (JWST) is estimated to observe objects as far as z = 15 with 100 times the sensitivity of the Hubble Space Telescope (HST). Several previous simulations have predicted the characteristics of the JWST deep field images using assumptions of universe geometry, the galaxy number densities, and the evolutions of high-z galaxies. While the assumptions made by these previous simulations are based on initial conditions defined by recent observations, the corresponding ranges of uncertainty in their measurements can lead to substantially different results. This study presents a novel geometric-focused deep field simulation using an ensemble approach to demonstrate the high variability in results due to the uncertainty ranges of the measurements used as initial conditions. A parameter sensitivity ensemble was run perturbing each initial condition individually through its range of uncertainty to determine which initial condition range of uncertainty has the largest effect on the resulting simulation. A 1000-member ensemble was run perturbing the initial conditions through their ranges of uncertainty obtained from recent estimates. A galaxy coverage percentage was calculated for each ensemble member and averaged together. The Apparent Galaxy Wall (AGW) effect is introduced and defined as >= 50% of a deep field image occupied by galaxies. A one-way one-sample t-test was conducted to conclude the JWST is likely to observe the AGW effect with an estimated galaxy coverage percentage of 55.12 +/- 30.30%. This study finds the most sensitive parameter to changes within its range of uncertainty is the estimated number of unseen galaxies in the HUDF. A discussion is included on the potential impacts of the AGW effect being observed and its potential to form a pseudo-cosmological horizon that may inhibit the effectiveness of future observatories.
M. Sailer
Thu, 30 Sep 21
50/82
Comments: 22 pages, 11 figures, 3 tables