Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-01-15
Astrophys.J.660:1186-1197,2007
Astronomy and Astrophysics
Astrophysics
12 pages + 9 figures. Accepted for publication in ApJ
Scientific paper
10.1086/513090
From a quantitative analysis of 413 Virgo cluster early-type dwarf galaxies (dEs) with Sloan Digital Sky Survey imaging data, we find that the dE class can be divided into multiple subpopulations that differ significantly in their morphology and clustering properties. Three dE subclasses are shaped like thick disks and show no central clustering: (1) dEs with disk features like spiral arms or bars, (2) dEs with central star formation, and (3) ordinary, bright dEs that have no or only a weak nucleus. These populations probably formed from infalling progenitor galaxies. In contrast, ordinary nucleated dEs follow the picture of classical dwarf elliptical galaxies in that they are spheroidal objects and are centrally clustered like E and S0 galaxies, indicating that they have resided in the cluster since a long time, or were formed along with it. These results define a morphology-density relation within the dE class. We find that the difference in the clustering properties of nucleated dEs and dEs with no or only a weak nucleus is not caused by selection biases, as opposed to previously reported suggestions. The correlation between surface brightness and observed axial ratio favors oblate shapes for all subclasses, but our derivation of intrinsic axial ratios indicates the presence of at least some triaxiality. We discuss possible interrelations and formation mechanisms (ram-pressure stripping, tidally induced star formation, harassment) of these dE subpopulations.
Binggeli Bruno
Glatt Katharina
Grebel Eva Katharina
Lisker Thorsten
No associations
LandOfFree
Virgo cluster early-type dwarf galaxies with the Sloan Digital Sky Survey. III. Subpopulations: distributions, shapes, origins 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 Virgo cluster early-type dwarf galaxies with the Sloan Digital Sky Survey. III. Subpopulations: distributions, shapes, origins, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Virgo cluster early-type dwarf galaxies with the Sloan Digital Sky Survey. III. Subpopulations: distributions, shapes, origins will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-187949