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arXiv · 1712.03944

$\nu\scriptstyle{\rm CO}N{\rm CEPT}$: Cosmological neutrino simulations from the non-linear Boltzmann hierarchy

Jeppe Dakin·Jacob Brandbyge·Steen Hannestad·Troels Haugbølle·Thomas Tram
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Abstract

In this paper the non-linear effect of massive neutrinos on cosmological structures is studied in a conceptually new way. We have solved the non-linear continuity and Euler equations for the neutrinos on a grid in real space in $N$-body simulations, and closed the Boltzmann hierarchy at the non-linear Euler equation using the stress and pressure perturbations from linear theory. By comparing with state-of-the art cosmological neutrino simulations, we are able to simulate the non-linear neutrino power spectrum very accurately. This translates into a negligible error in the matter power spectrum, and so our $\scriptstyle{\rm CO}N{\rm CEPT}$ code is ideally suited for extracting the neutrino mass from future high precision non-linear observational probes such as Euclid.

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Jeppe Dakin, Jacob Brandbyge, Steen Hannestad, Troels Haugbølle, Thomas Tram. 2017-12-11. $\nu\scriptstyle{\rm CO}N{\rm CEPT}$: Cosmological neutrino simulations from the non-linear Boltzmann hierarchy. https://doi.org/10.1088/1475-7516%2F2019%2F02%2F052

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