A Model of the Cosmic Infrared Background Produced by Distant Galaxies

TL;DR

This paper presents a simulation-based model of the cosmic infrared background from distant galaxies, analyzing its impact on telescope sensitivity and revealing the large-scale structure of the universe.

Contribution

It introduces a new simulation model of the infrared background based on large-scale structure and dark matter halo evolution, matching observational data.

Findings

Confusion limit is significantly lower for larger telescopes.

Infrared background maps reflect large-scale cosmic structure.

Fluctuations in intensity peaks are not correlated with superclusters.

Abstract

The extragalactic background radiation produced by distant galaxies emitting in the far infrared limits the sensitivity of telescopes operating in this range due to confusion. We have constructed a model of the infrared background based on numerical simulations of the large-scale structure of the Universe and the evolution of dark matter halos. The predictions of this model agree well with the existing data on source counts. We have constructed maps of a sky field with an area of 1 deg$^2$ directly from our simulated observations and measured the confusion limit. At wavelengths $100-300$ $\mu$m the confusion limit for a 10-m telescope has been shown to be at least an order of magnitude lower than that for a 3.5-m one. A spectral analysis of the simulated infrared background maps clearly reveals the large-scale structure of the Universe. The two-dimensional power spectrum of these maps has turned out to be close to that measured by space observatories in the infrared. However, the fluctuations in the number of intensity peaks observed in the simulated field show no clear correlation with superclusters of galaxies; the large-scale structure has virtually no effect on the confusion limit.