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arXiv · 1705.08165

COLA with massive neutrinos

Bill S. Wright·Hans A. Winther·Kazuya Koyama
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Abstract

The effect of massive neutrinos on the growth of cold dark matter perturbations acts as a scale-dependent Newton's constant and leads to scale-dependent growth factors just as we often find in models of gravity beyond General Relativity. We show how to compute growth factors for $\Lambda$CDM and general modified gravity cosmologies combined with massive neutrinos in Lagrangian perturbation theory for use in COLA and extensions thereof. We implement this together with the grid-based massive neutrino method of Brandbyge and Hannestad in $\texttt{MG-PICOLA}$ and compare COLA simulations to full $\it N$-body simulations of $\Lambda$CDM and $f(R)$ gravity with massive neutrinos. Our implementation is computationally cheap if the underlying cosmology already has scale-dependent growth factors and it is shown to be able to produce results that match $\it N$-body to percent level accuracy for both the total and CDM matter power-spectra up to $k\lesssim 1 h/$Mpc.

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Bill S. Wright, Hans A. Winther, Kazuya Koyama. 2017-05-23. COLA with massive neutrinos. https://doi.org/10.1088/1475-7516%2F2017%2F10%2F054

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