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Data Visualization (images & movies from Numerical Simulation projects)

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Introduction

This page include simulations of:

• InterGalactic Medium
• Hydrodynamic simulations with radiative cooling
• SPH/N-body Simulations of Clusters (formation of a cluster size dark halo by collisional and collisionless dark matter)

Data

Simulations of InterGalacticMedium

Tom Theuns and his collaborators are studying the evolution of the Ly_alpha forests at high redshifts.

Pic.1 Gas density distribution in a volume of size 11x11x1.35 (h^-1Mpc)³. High density regions are yellow, low density regions are black. The mass resolution is 1.5 x 10⁶ Msun. The gas has a characteristic filamentary appearance, with high density knots corresponding to forming galaxies at the intersection of two or more filaments.

larger format:
gzipped ps (150 KB)
GIF format(120KB)

Credit: Tom Theuns, ref.1

Pic.2 Same as Pic.1, z=5.0.

larger format:
PS format(180KB)
GIF format(140KB)

Credit: Tom Theuns, ref.1

Hydrodynamic simulation with radiative cooling

Yoshida et al. (2002, see the reference below) used two techniques for following gas cooling in simulations of galaxy formation, and compared the results such as `galaxy' (cold dense gas) masses and their positions.

Pic.1 Projected gas distribution in a box of 15 h-1Mpc

larger format:
PS format(150KB)
GIF format(120KB)

Credit: See ref.2

Pic.2 The distribution of the `galaxies' in the hydrodynamic and semianalytic simulations. The blue-white color scale shows the underlying matter distribution.

SPH simulation (left) and the semi-analytic model (right)

Credit: See ref.2

SPH/N-body Simulations of Clusters

Formation of a cluster size dark halo by collisional and collisionless dark matter

Pic.1 Projected mass distributions in a cube box 15 Mpc/h per oneside (left column) and in the central regions of 2 Mpc/h per one side (enlarged, right column). The picture clearly shows the difference (as well as similarlities in the outer region of the halo) in mass distribution, morphorlogy of the central part, and abundance of subclumps.

larger version gzipped PS format

Credit: See ref. 3 - 4

References

1. P3M-SPH simulations of the Ly-alpha forest
   T.Theuns, A.Leonard, J.Schaye, G.Efstathiou, F.Pearce, and P.Thomas
   1998, MNRAS, 301, 478
2. Gas cooling in simulations of the formation of the galaxy population
   N. Yoshida, F. Stoehr, V. Springel, and S.D.M. White
   2002, astro-ph/0202341
   
3. Collisional dark matter and the structure of dark halos
   N.Yoshida, V.Springel, S.D.M.White, G.Tormen
   2000, ApJ, 535, L103 (preprint astro-ph/0002362)
4. Weakly self-interacting dark matter and the structure of dark halos
   N.Yoshida, V.Springel, S.D.M.White, G.Tormen
   2000, ApJ, 544, L87 (preprint astro-ph/0006134)
   

Credit

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/sim_gas/index.shtml"

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