2005/11/24 by Takayuki R. Saitoh, Jin Koda, Takashi Okamoto +2
Physics and Astronomy · #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/500104
published as Astrophys.J.640:22-30,2006 · 9page, 13 figures. Accepted for publication in ApJ. A high-resolution PDF of the paper can be obtained from http://th.nao.ac.jp/~takayuki/ApJ05/
arxiv created 2005/11/24 · openalex publication_date 2006/03/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Tidal disruption of dark matter halos around proto-globular clusters in the halo of a small galaxy is studied in the context of the hierarchical clustering scenario by using semicosmological N -body/SPH simulations assuming the standard cold dark matter model (Ω 0 = 1). Our analysis on the formation and evolution of the galaxy and its substructures continues until z = 2.0. In such a high-redshift universe, the Einstein-de Sitter universe is still a good approximation for the recently favored Λ-dominated universe, and thus our results do 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 × 10 3 M ☉ ). Because of the cooling, each clump immediately forms a "core-halo" structure that 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, these clumps get dominated by baryons. Once a clump is captured by the host halo, its mass drastically decreases with 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.