A James Webb Space Telescope NIRCam Deep Field Simplified Simulation Using a Geometric-Focused Ensemble Approach

TL;DR

This paper introduces a simplified geometric ensemble simulation approach to predict JWST deep field images, highlighting high variability due to observational uncertainties and discussing the potential impact of the Apparent Galaxy Wall effect.

Contribution

It presents a novel ensemble simulation method focusing on geometric aspects to assess variability in JWST deep field predictions, emphasizing the role of observational uncertainties.

Findings

High variability in galaxy coverage estimates due to uncertainty ranges.

JWST unlikely to observe the Apparent Galaxy Wall effect with current estimates.

Discussion on how the AGW effect could influence future cosmological observations.

Abstract

Recent studies predict the characteristics of JWSTs deep field image using a deterministic approach based on recent observational measurements with corresponding ranges of uncertainty. This study presents a simplified geometric-focused deep field simulation using an ensemble approach to demonstrate the high variability in results due to the uncertainty ranges of observational measurements. Two sets of ensemble simulations were conducted: a parameter sensitivity ensemble, and a 90-member full ensemble each calculating the percentage of the image occupied by galaxies. The estimated number of unseen galaxies in the HUDF was found to provide the largest variability of results. The Apparent Galaxy Wall (AGW) effect is introduced and defined as >= 50% area of a deep field image occupied by galaxies. A one-way one-sample t-test was conducted on the 90-member ensemble, concluding the JWST is not likely to observe the AGW effect with an estimated galaxy coverage percentage of 47.07% +/- 31.85 but does not rule out the effect as a possibility. 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.