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-Introduction
-Simulation Parameters
-Data Download
-References
-Credit

linkData Visualization (images & movies from Numerical Simulation projects)

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Introduction

Two cosmological models were simulated in larger boxes (479 Mpc/h for LCDM and 321 Mpc/h for tCDM) than those of the Virgo simulations, while keeping a high mass resolution. We find many clusters in the box, which are still well resolved and thus suitable for re-simulation. The main projects associated with these simulations are:

Cluster Resimulation Project

Topology of the Universe

Large Scale Motions in Superclusters and the Sunyaev-Zel'dovich effect

Ray-tracing simulations of gravitational Lensing

Simulation parameterstop


Shown in the left panels are projected mass distibutions in a sliced region in the simulation box. Low-density regions which look like "voids" are dark, while blue and red parts are high-density regions. The pictures were created using an SPH smoothing scheme which assigns to each particle an individual smoothing length

 

lCDMBoxsize 479 Mpc/h
5123 particles
OMEGA = 0.3
LAMBDA = 0.7
H0 = 70 km/(Mpc sec)
Sigma8 = 0.9
Mass per particle 6.86 x 1010M_sun/h

 

 

 

tCDMBoxsize 320.6 Mpc/h
5123 particles
OMEGA = 1.0
LAMBDA = 0.0
H0 = 50 km/(Mpc sec)
Sigma8 = 0.51
Mass per particle 6.86 x 1010M_sun/h

 

 

 

Model Omega0 lambda h Gamma Sigma8 Npar L (Mpc/h) mp (M_sun/h) l_soft (Kpc/h)
tCDM 1.0 0.0 0.5 0.21 0.51 5123 320.6 6.86 x 1010 30
LCDM 0.3 0.7 0.7 0.21 0.90 5123 479.0 6.86 x 1010 30

 

Data Downloadtop

Available data

Snaphot outputs at 6 different redshifts for the 2 models.
The size of one compressed data file is approximately 150MB-190MB. A single snapshot output consists of 8 files for particles positions and 8 files for velocities. The tCDM model data are available only on tapes for ordering.
Select cosmological model and redshift

-- AND download --

-- OR   order --

Credit: An example of proper credit for these Virgo data

Referencestop


Non-Gaussian CMB Temperature Fluctuations from Peculiar Velocities of Clusters
N. Yoshida, R. Sheth, and A. Diaferio, 2001, MNRAS, 328, 669

The mass functions of dark matter halos
A. Jenkins, C. S. Frenk, S. D. M. White, J. M. Colberg, S. Cole, A. E. Evrard, H.M.P. Couchman, and N. Yoshida, 2001, MNRAS, 321, 372

A New Parallel P3M Code Very Large Cosmological Simulations
T. MacFarland, H. M. P. Couchman, F. R. Pearce, J. Pichlmeier, 1998, New Astronomy, 3, 687

Credittop

Here is an example of proper credit for these Virgo data.
"The simulations in this paper were carried out by the Virgo Supercomputing Consortium using computers based at Computing Centre of the Max-Planck Society in Garching and at the Edinburgh Parallel Computing Centre. The data are publicly available at www.mpa-garching.mpg.de/galform/virgo/vls"

Comments to: Virgo Administrator virgo@mpa-garching.mpg.detop