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arXiv · 0812.2253

The nonlinear probability distribution function in models with local primordial non-Gaussianity

Tsz Yan Lam·Ravi K. Sheth
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Abstract

We use the spherical evolution approximation to investigate nonlinear evolution from the non-Gaussian initial conditions characteristic of the local f_nl model. We provide an analytic formula for the nonlinearly evolved probability distribution function of the dark matter which shows that the under-dense tail of the nonlinear PDF in the f_nl model should differ significantly from that for Gaussian initial conditions. Measurements of the under-dense tail in numerical simulations may be affected by discreteness effects, and we use a Poisson counting model to describe this effect. Once this has been accounted for, our model is in good quantitative agreement with the simulations.

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Tsz Yan Lam, Ravi K. Sheth. 2008-12-11. The nonlinear probability distribution function in models with local primordial non-Gaussianity. https://doi.org/10.1111/j.1365-2966.2009.14672.x

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