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arXiv · 1402.2336

Higher moments of primordial non-Gaussianity and N-body simulations

Saroj Adhikari·Sarah Shandera·Neal Dalal
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Abstract

We perform cosmological N-body simulations with non-Gaussian initial conditions generated from two independent fields. The dominant contribution to the perturbations comes from a purely Gaussian field, but we allow the second field to have local non-Gaussianity that need not be weak. This scenario allows us to adjust the relative importance of non-Gaussian contributions beyond the skewness, producing a scaling of the higher moments different from (and stronger than) the scaling in the usual single field local ansatz. We compare semi-analytic prescriptions for the non-Gaussian mass function, large scale halo bias, and stochastic bias against the simulation results. We discuss applications of this work to large scale structure measurements that can test a wider range of models for the primordial fluctuations than is usually explored.

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Saroj Adhikari, Sarah Shandera, Neal Dalal. 2014-06-23. Higher moments of primordial non-Gaussianity and N-body simulations. https://doi.org/10.1088/1475-7516%2F2014%2F06%2F052

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