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arXiv · 1606.06167

Simulating nonlinear cosmological structure formation with massive neutrinos

Arka Banerjee·Neal Dalal
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Abstract

We present a new method for simulating cosmologies that contain massive particles with thermal free streaming motion, such as massive neutrinos or warm/hot dark matter. This method combines particle and fluid descriptions of the thermal species to eliminate the shot noise known to plague conventional N-body simulations. We describe this method in detail, along with results for a number of test cases to validate our method, and check its range of applicability. Using this method, we demonstrate that massive neutrinos can produce a significant scale-dependence in the large-scale biasing of deep voids in the matter field. We show that this scale-dependence may be quantitatively understood using an extremely simple spherical expansion model which reproduces the behavior of the void bias for different neutrino parameters.

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Arka Banerjee, Neal Dalal. 2016-06-20. Simulating nonlinear cosmological structure formation with massive neutrinos. https://doi.org/10.1088/1475-7516%2F2016%2F11%2F015

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