# Benjamin L’Huillier(벤자민)

Cosmologist and Astrophysicist, Research Fellow at KASI, Daejeon, South Korea

## Horizon Run 4

J. Kim, C. Park, B. L'Huillier, & S. E. Hong, 2015, JKAS 48, 213, ADS

Cosmological simulations have long been used to understand structure formation. The Horizon run 4 is our latest run, using a WMAP5 cosmology, with $6300^3$ particles in a $3150\,h^{-1}$ Mpc box, and the use of second order perturbation theory (2LPT) initial conditions, makes it ideal to simulate the cosmological evolution of haloes more massive than about $2\times 10^{11}\,h^{-1}\,\mathrm{M}_\odot$.
Haloes were detected with a parallel version of the Friends-of-friends (FoF) algorithm, and the subhaloes were detected using the Physically Self-Bound (PSB) method (Kim & Park 2006). 70 outputs were saved and a merger tree was built to follow the halo histories. Light-cone data have also been saved until $z=1.39$.
The background of this page is a $1.5\,h^{-1}\,\mathrm{Mpc}$-wide density slice in a logarithmic scale from the HR4 simulation at $z=0$.