Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-09-22
Astronomy and Astrophysics
Astrophysics
12 Pages, Review article to appear in the proceedings of "Island Universes: Structure and Evolution of Disk Galaxies" (Tersche
Scientific paper
I briefly review the growing evidence that thick stellar disks surround most edge-on disk galaxies. Recent studies show that these extragalactic thick disks have old ages, low metallicities, long scale lengths, and moderately flattened axial ratios, much like the thick disk of the Milky Way. However, the properties of thick disks change systematically with the mass of the galaxy. The thick disks of low mass galaxies are more prominent and somewhat more metal-poor than those surrounding massive disk galaxies. Given the strong evidence that thick disks are fossils from an early epoch of merging, these trends place tight constraints on the early assembly of disk galaxies. The data suggest that the vast majority of the accretion onto the early disk was gaseous, but that the majority of thick disk stars were directly accreted.
Dalcanton Julianne J.
Seth Anil
Yoachim Peter
No associations
LandOfFree
Extragalactic Thick Disks: Implications for Early Galaxy Evolution does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Extragalactic Thick Disks: Implications for Early Galaxy Evolution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Extragalactic Thick Disks: Implications for Early Galaxy Evolution will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-71755