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arXiv · 1901.09210

Transients from Initial Conditions Based on Lagrangian Perturbation Theory in $N$-body Simulations III: The Case of GADGET-2 Code

Takayuki Tatekawa
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Abstract

In modern cosmology, the precision of the theoretical prediction is increasingly required. In cosmological $N$-body simulations, the effect of higher-order Lagrangian perturbation on the initial conditions appears in terms of statistical quantities of matter density field. We have considered the effect of third-order Lagrangian perturbation (3LPT) on the initial conditions, which can be applied to Gadget-2 code. Then, as statistical quantities, non-Gaussianity of matter density field has been compared between cases of different order perturbations for the initial conditions. Then, we demonstrate the validity of the initial conditions with second-order Lagrangian perturbation (2LPT).

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Takayuki Tatekawa. 2019-01-26. Transients from Initial Conditions Based on Lagrangian Perturbation Theory in $N$-body Simulations III: The Case of GADGET-2 Code. https://doi.org/10.1142/s0218271820500960

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