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arXiv · 2107.10815

Contributions from primordial non-Gaussianity and General Relativity to the galaxy power spectrum

Rebeca Martinez-Carrillo·Juan Carlos Hidalgo·Karim A. Malik·Alkistis Pourtsidou
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Abstract

We compute the real space galaxy power spectrum, including the leading order effects of General Relativity and primordial non-Gaussianity from the $f_{\mathrm{NL}}$ and $g_{\mathrm{NL}}$ parameters. Such contributions come from the one-loop matter power spectrum terms dominant at large scales, and from the factors of the non-linear bias parameter $b_{\mathrm{NL}}$ (akin to the Newtonian $b_{\phi}$). We assess the detectability of these contributions in Stage-IV surveys. In particular, we note that specific values of the bias parameter may erase the primordial and relativistic contributions to the configuration space power spectrum.

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Rebeca Martinez-Carrillo, Juan Carlos Hidalgo, Karim A. Malik, Alkistis Pourtsidou. 2021-07-22. Contributions from primordial non-Gaussianity and General Relativity to the galaxy power spectrum. https://doi.org/10.1088/1475-7516%2F2021%2F12%2F025

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