Issue |
EAS Publications Series
Volume 10, 2003
JENAM 2002, Galactic & Stellar Dynamics
|
|
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Page(s) | 133 - 133 | |
DOI | https://doi.org/10.1051/eas2003159 | |
Published online | 22 December 2003 |
C. Boily, P. Patsis, S. Portegies Zwart, R. Spurzem and C. Theis (eds)
EAS Publications Series, 10 (2003) 133
The mechanics of dark matter halo formation
1
Observatoire Astronomique, 11 rue de l'Université, 67000 Strasbourg, France
2
Astronomisches Rechen-Institut, Mönchhofstrasse 12-14, 69120 Heidelberg, Germany
3
Max-Planck-Institut für Astronomie, Königstuhl, 69117 Heidelberg, Germany
and SGI Japan Ltd.,
668-3, Moto-zaimoku-cho, Fushimi-ku,
Kyoto 612-8043, Japan
We study the survival of sub-structures (clumps) within larger self-gravitating galaxies or dark matter halos. Building on scaling relations obtained from N-body calculations of violent relaxation, we argue that the tidal field of galaxies and halos can only destroy sub-structures if spherical symmetry is imposed at formation. Unless the larger halo is built up from a few large clumps, we find that clump-clump encounters are unlikely to homogenise the halo on a dynamical timescale. Phase-mixing would proceed faster in the inner parts and allow for the secular evolution of a stellar disc.
© EAS, EDP Sciences, 2003