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arXiv · 1801.05570

A Clustered Extragalactic Foreground Model for the EoR

Steven Murray·Cathryn Trott·Christopher Jordan
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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.

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Steven Murray, Cathryn Trott, Christopher Jordan. 2018-01-17. A Clustered Extragalactic Foreground Model for the EoR. https://doi.org/10.1017/s174392131701119x

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