Neutrinos in non-linear structure formation — a simple SPH approach

Steen Hannestad; Troels Haugbølle; Christian Schultz

doi:10.1088/1475-7516/2012/02/045

Neutrinos in non-linear structure formation — a simple SPH approach

Steen Hannestad, Troels Haugbølle, Christian Schultz

13 Citations (Scopus)

Abstract

We present a novel method for implementing massive neutrinos in N-body simulations. Instead of sampling the neutrino velocity distribution by individual point particles we take neutrino free-streaming into account by treating it as an effective redshift dependent sound speed in a perfect isothermal fluid, and assume a relation between the sound speed and velocity dispersion of the neutrinos. Although the method fails to accurately model the true neutrino power spectrum, it is able to calculate the total matter power spectrum to the same accuracy as more complex hybrid neutrino methods, except on very small scales. We also present an easy way to update the publicly available GADGET-2 version with this neutrino approximation.

Original language	English
Article number	045
Journal	Journal of Cosmology and Astroparticle Physics
Volume	2
Number of pages	13
ISSN	1475-7516
DOIs	https://doi.org/10.1088/1475-7516/2012/02/045
Publication status	Published - Feb 2012

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10.1088/1475-7516/2012/02/045

Cite this

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