Tidal disruption of dark matter halos around proto-globular clusters in a halo of a small galaxy is studied in the context of the hierarchical clustering scenario by using semi-cosmological N-body/SPH simulations assuming the standard cold dark matter model ( \Omega _ { 0 } = 1 ) .
Our analysis on formation and evolution of the galaxy and its substructures archives until z = 2.0 .
In such a high-redshift universe , the Einstein-de Sitter universe is still a good approximation for a recently favored \Lambda -dominated universe , and then our results does not depend on the choice of cosmology .
In order to resolve small gravitationally-bound clumps around galaxies and consider radiative cooling below T = 10 ^ { 4 } K , we adopt a fine mass resolution ( m _ { SPH } = 1.12 \times 10 ^ { 3 } M _ { \odot } ) .
Because of the cooling , each clump immediately forms a ‘ core-halo ’ structure which consists of a baryonic core and a dark matter halo .
The tidal force from the host galaxy mainly strips the dark matter halo from clumps and , as a result , theses clumps get dominated by baryons .
Once a clump is captured by the host halo , its mass drastically decreases each pericenter passage .
At z = 2 , more than half of the clumps become baryon dominated systems ( baryon mass/total mass > 0.5 ) .
Our results support the tidal evolution scenario of the formation of globular clusters and baryon dominated dwarf galaxies in the context of the cold dark matter universe .