1998/09/24 by R. Dominguez-Tenreiro, R. Domínguez-Tenreiro, P. B. Tissera +2 · 1 citation
Physics and Astronomy · #Angular momentum #Angular momentum coupling #Angular momentum of light #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Baryon #Bulge #Galaxies: Formation, Evolution, Phenomena #Specific relative angular momentum #Star formation #Total angular momentum quantum number #astro-ph
paper · pdf · doi:10.1086/311733
11 pages, 2 figures. Accepted by The Astrophysical Journal Letters
arxiv created 1998/09/24 · openalex publication_date 1998/12/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report results on the formation of disklike structures in two cosmological hydrodynamical simulations, which share the same initial conditions, in a hierarchical clustering scenario. In the first simulation, a simple and generic implementation of star formation has allowed galaxy-like objects with stellar bulges and extended, populated disks to form. Gas in the disk comes both from particles that survive mergers, keeping in part their angular momentum content, and from new gas supplied by infall once the merger process is over, with global specific angular momentum conservation. The stellar bulge forms from gas that has lost most of its angular momentum. In the second simulation, no star formation has been included. In this case, objects consist of an overpopulated central gas concentration and an extended, underpopulated disk. The central concentration forms from particles that suffer an important angular momentum loss in violent events, and it often contains more than 70% of the object's baryonic mass. The external disk forms by late infall of gas that roughly conserves its specific angular momentum. The difference between these two simulations is likely to be due to the stabilizing character of the stellar bulge-like cores that form in the first simulation, which diminishes the inflow of gas triggered by mergers and interactions.