Galaxy Assembly
| dc.creator | Bell, Eric F. | |
| dc.date | 2004-08-02 | |
| dc.date | 2004-08-25 | |
| dc.date.accessioned | 2026-07-07T02:14:11Z | |
| dc.date.available | 2026-07-07T02:14:11Z | |
| dc.description | In a Lambda CDM Universe, galaxies grow in mass both through star formation and through addition of already-formed stars in galaxy mergers. Because of this partial decoupling of these two modes of galaxy growth, I discuss each separately in this biased and incomplete review of galaxy assembly; first giving an overview of the cosmic-averaged star formation history, and then moving on to discuss the importance of major mergers in shaping the properties of present-day massive galaxies. The cosmic-averaged star formation rate, when integrated, is in reasonable agreement with the build-up of stellar mass density. Roughly 2/3 of all stellar mass is formed during an epoch of rapid star formation prior to z=1, with the remaining 1/3 formed in the subsequent 9 Gyr during a period of rapidly-declining star formation rate. The epoch of important star formation in massive galaxies is essentially over. In contrast, a significant fraction of massive galaxies undergo a major merger at z<1, as evidenced by close pair statistics, morphologically-disturbed galaxy counts, and the build-up of stellar mass in morphologically early-type galaxies. Each of these methods is highly uncertain; yet, taken together, it is not implausible that the massive galaxy population is strongly affected by late galaxy mergers, in excellent qualitative agreement with our understanding of galaxy evolution in a Lambda CDM Universe. | |
| dc.description | 23 pages, 6 embedded figures. Invited review to appear in Planets to Cosmology: Essential Science in Hubble's Final Years, ed. M. Livio (Cambridge: CUP), in press (2005). Removed figure 5; added references and discussion; conclusions unchanged | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0408023 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0408023 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/8020 | |
| dc.subject | Astrophysics | |
| dc.title | Galaxy Assembly | |
| dc.type | text |