The Emergence of the Thick Disk in a Cold Dark Matter Universe
Abstract
The disk galaxy simulated using our chemodynamic galaxy formation code, GCD+, is shown to have a thick-disk component. This is evidenced by the velocity dispersion versus age relation for solar neighborhood stars, which clearly shows an abrupt increase in velocity dispersion at a look-back time of approximately 8 Gyr, and is in excellent agreement with observation. These thick-disk stars are formed from gas that is accreted to the galaxy during a chaotic period of hierarchical clustering at high redshift. This formation scenario is shown to be consistent with observations of both the Milky Way and extragalactic thick disks.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2004
- DOI:
- 10.1086/422709
- arXiv:
- arXiv:astro-ph/0405306
- Bibcode:
- 2004ApJ...612..894B
- Keywords:
-
- Galaxies: Evolution;
- Galaxies: Formation;
- Galaxy: Disk;
- Astrophysics
- E-Print:
- accepted for publication in ApJ