Scientific Purpose

The Horizon Runs (HRs) are a series of massive $N$-body and hydrodynamic simulations realized at the Korea Institute for Advanced Study to study cosmology and galaxy formation and evolution.

The first Horizon Run, published in 2009 in support of the SDSS-III survey, was the largest $N$-body simulation at the time of publication. It used $4120^3$ = 69.9 billion particles in a volume of $(6.592 h^{-1}\mathrm{Gpc})^3$

The Horizon Runs 2 and 3 were published in 2011, were made using $6000^3$ = 216 billions and $7210^3$ = 374 billion particles, spanning a volume of $(7.200 h^{-1} \mathrm{Gpc})^3$ and $(10.815 h^{-1} \mathrm{Gpc})^3$, respectively. These simulations improve on our previous Horizon Run 1 (HR1) up to a factor of 4.4 in volume, and range from 2600 to over 8800 times the volume of the Millennium Run. In addition, they achieve a considerably finer mass resolution, down to $1.25\times 10^{11} h^{-1}M_\odot$, allowing to resolve galaxy-size halos with mean particle separations of $1.2 $ and $1.5h^{-1} \mathrm{Mpc}$, respectively.

The Horizon Run 4, published in 2015, uses $6300^3$ particles in a $3150 h^{-1} \mathrm{Mpc}$ box, and aims to study galaxy evolution in their cosmological context.

The Horizon Run 5, submitted in 2020, is the most largest cosmological hydrodynamic simulation with $1041 \mathrm{cMpc}$ box, and aims to study the effect of large-scale perturbations on formation of galaxies and clusters.

Reference papers


The following people have been involved in the development and analyzis of the Horizon Runs.

Cosmological model of the Horizon Runs (HR's)

All the HR's share the same cosmology, but the HR5 reflects recent updates of the Planck observation.

Cosmology used for the HR1-4's
Cosmological model $\Omega_{m,0}$ $\Omega_{b,0}$ $\Omega_{\Lambda,0}$ $n_\mathrm{s}$ $H_0\,\mathrm{(km/s/Mpc)}$ $\sigma_8$
$\Lambda$CDM WMAP5 0.26 0.044 0.74 0.96 72 1/1.26
Cosmology used for the HR5's
Cosmological model $\Omega_{m,0}$ $\Omega_{b,0}$ $\Omega_{\Lambda,0}$ $n_\mathrm{s}$ $H_0\,\mathrm{(km/s/Mpc)}$ $\sigma_8$
$\Lambda$CDM Planck 0.3 0.047 0.7 - 68.4 1/1.225

Simulations specifics
Simulations Name HR1 HR2 HR3 HR4 HR5
Box Size ($c\mathrm{Mpc}$) 9417 10285 15450 4436 1049
Number of CDM particles 4120$^3$ 6000$^3$ 7210$^3$ 6300$^3$ gas cells + particles
Starting redshift 23 32 27 100 200
Initial power spectrum generator Eisenstein & Hu (1998) CAMB Source CAMB Source CAMB Source CAMB Source
Initial displacement Zel'dovich Zel'dovich Zel'dovich 2LPT 2LPT
(Dubinski, Kim, Park 2004)
(Teyssier 2002)

Pictures & Movies


List of papers using the HR's data

  1. L'Huillier, Benjamin; Park, Changbom; Kim, Juhan (2016) MNRAS in press
    The ecology of dark matter haloes -II. Effect of the environment on the alignment of halo pairs
  2. Li, Xiao-Dong; Park, Changbom; Sabiu, Cristiano G.; Park, Hyunbae; Weinberg, David H.; Schneider, Donald P.; Kim, Juhan; Hong, Sungwook E. (2016) ApJ. Accepted.
    Cosmological constraints from the redshift dependence of the Alcock-Paczynski effect: application to the SDSS-III BOSS DR12 galaxies
  3. Uhlemann, C.; Codis, S.; Kim, J.; Pichon, C.; Bernardeau, F.; Pogosyan, D.; Park, C.; L'Huillier, B. (2016) MNRAS in press
    Beyond Kaiser bias: mildly non-linear two-point statistics of densities in distant spheres
  4. Kopp, Michael; Uhlemann, Cora; Achitouv, Ixandra (2016) arXiv:1606.02301
    Choose to smooth: Gaussian streaming with the truncated Zel'dovich approximation
  5. Anderson, P.; Davis, T. M.; Howlett, C. (2016) MNRAS 463, 4083
    Cosmology with peculiar velocities: observational effects
  6. Hong, Sungwook E.; Park, Changbom; Kim, Juhan (2016) ApJ 823, 103
    The Most Bound Halo Particle-Galaxy Correspondence Model: Comparison between Models with Different Merger Timescales
  7. Hwang, Ho Seong; Geller, Margaret J.; Park, Changbom; Fabricant, Daniel G.; Kurtz, Michael J.; Rines, Kenneth J.; Kim, Juhan; Diaferio, Antonaldo; Zahid, H. Jabran; Berlind, Perry; Calkins, Michael; Tokarz, Susan; Moran, Sean (2016) ApJ 818, 173
    HectoMAP and Horizon Run 4: Dense Structures and Voids in the Real and Simulated Universe
  8. Clampitt, Joseph; Jain, Bhuvnesh; Sánchez, Carles (2016) MNRAS 456, 4425
    Clustering and bias measurements of SDSS voids
  9. Kumar, Abhinav; Wang, Yuyu; Feldman, Hume A.; Watkins, Richard (2015) arXiv:1512.08800
    Gravitational potential wells and the cosmic bulk flow
  10. Uhlemann, Cora; Kopp, Michael; Haugg, Thomas (2015) Phys. Rev. D 92, 063004
    Edgeworth streaming model for redshift space distortions
  11. Kim, Juhan; Park, Changbom; L'Huillier, Benjamin; Hong, Sungwook E. (2015) JKAS 48, 213
    Horizon Run 4 Simulation: Coupled Evolution of Galaxies and Large-scale Structures of the Universe
  12. L'Huillier, Benjamin; Park, Changbom; Kim, Juhan (2015) MNRAS 451, 527.
    The ecology of dark matter haloes -I. The rates and types of halo interactions
  13. Li, Xiao-Dong; Park, Changbom; Forero-Romero, J. E.; Kim, Juhan (2015) ApJ 796, 137.
    Cosmological constraints from the redshift dependence of the Alcock-Paczynski test and volume effect: galaxy two-point correlation function
  14. Speare, Robert; Gott, J. Richard; Kim, Juhan; Park, Changbom (2015) ApJ 799, 176.
    Horizon Run 3: Topology as a Standard Ruler
  15. Li, Xiao-Dong; Park, Changbom; Forero-Romero, J. E.; Kim, Juhan (2014) ApJ 796, 137.
    Cosmological Constraints from the Redshift Dependence of the Alcock-Paczynski Test: Galaxy Density Gradient Field
  16. Kim, Young-Rae; Choi, Yun-Young; Kim, Sungsoo S.; Kim, Kap-Sung; Lee, Jeong-Eun; Shin, Jihye; Kim, Minbae (2014) ApJS 212, 22.
    Systematic Effects on the Genus Topology of the Large-scale Structure of the Universe
  17. Choi, Yun-Young; Kim, Juhan; Rossi, Graziano; Kim, Sungsoo S.; Lee, Jeong-Eun (2013) ApJS 209, 19.
    Topology of Luminous Red Galaxies from the Sloan Digital Sky Survey
  18. Park, Changbom; Choi, Yun-Young; Kim, Juhan; Gott, J. Richard, III; Kim, Sungsoo S.; Kim, Kap-Sung (2012) ApJL 759, L7.
    The Challenge of the Largest Structures in the Universe to Cosmology
  19. Kim, Juhan; Park, Changbom; Rossi, Graziano; Lee, Sang Min; Gott, J. Richard, III (2011) JKAS 44, 217.
    The New Horizon Run Cosmological N-Body Simulations
  20. Kim, Juhan; Park, Changbom; Gott, J. Richard, III; Dubinski, John (2009) ApJ 701, 1547.
    The Horizon Run N-Body Simulation: Baryon Acoustic Oscillations and Topology of Large-scale Structure of the Universe