A Clustered Extragalactic Foreground Model for the EoR

TL;DR

This paper refines a statistical model of extragalactic foregrounds for Epoch of Reionization studies by incorporating source clustering, showing that ignoring clustering is valid over certain scales due to Galactic synchrotron effects.

Contribution

It extends previous foreground models by including source clustering and demonstrates the validity of ignoring clustering at specific scales, contrasting prior findings.

Findings

Ignoring source clustering is valid over scales of $k ext{~}(0.6, 40.) h { m Mpc}^{-1}$.

Galactic synchrotron component shadows source clustering effects.

Contrasts with Murray 2017, reducing false detection risk.

Abstract

We review an improved statistical model of extra-galactic point-source foregrounds first introduced in [Murray 2017], in the context of the Epoch of Reionization. This model extends the instrumentally-convolved foreground covariance used in inverse-covariance foreground mitigation schemes, by considering the cosmological clustering of the sources. In this short work, we show that over scales of $k \sim (0.6, 40.) h {\rm Mpc}^{-1}$, ignoring source clustering is a valid approximation. This is in contrast to [Murray 2017], who found a possibility of false detection if the clustering was ignored. The dominant cause for this change is the introduction of a Galactic synchrotron component which shadows the clustering of sources.