other query modes : |
Identifier query |
Coordinate query |
Criteria query |
Reference query |
Basic query |
Script submission |
TAP |
Output options |
Object types |
Help |
2001MNRAS.326.1076D - Mon. Not. R. Astron. Soc., 326, 1076-1094 (2001/September-3)
The evolution and star formation of dwarf galaxies in the Fornax Cluster.
DRINKWATER M.J., GREGG M.D., HOLMAN B.A. and BROWN M.J.I.
Abstract (from CDS):
We classified the observed galaxies as late-type if we detected Hα emission at an equivalent width greater than 1Å. The spectra were obtained through fixed apertures, so they reflect activity in the galaxy cores, but this does not significantly bias the classifications of the compact dwarfs in our sample. The new classifications reveal a higher rate of star formation among the dwarf galaxies than suggested by morphological classification: 35 per cent have significant Hα emission indicative of star formations but only 19 per cent were morphologically classified as late-types.
The star-forming dwarf galaxies span the full range of physical sizes and we find no evidence in our data for a distinct class of star-forming blue compact dwarf (BCD) galaxy. The distribution of scale sizes is consistent with evolutionary processes which transform late-type dwarfs to early-type dwarfs. The fraction of dwarfs with active star formation drops rapidly towards the cluster centre: this is the usual density-morphology relation confirmed here for dwarf galaxies. The star-forming dwarfs are concentrated in the outer regions of the cluster, the most extreme in an infalling subcluster. We estimate gas depletion time-scales for five dwarfs with detected Hi emission: these are long (of order 1010yr), indicating that an active gas removal process must be involved if they are transformed into gas-poor dwarfs as they fall further into the cluster. Finally, in agreement with our previous results, we find no compact dwarf elliptical (M 32-like) galaxies in the Fornax Cluster.
Abstract Copyright: The Royal Astronomical Society
Journal keyword(s): stars: formation - galaxies: dwarf - galaxies: evolution - galaxies: clusters: individual: Fornax
Nomenclature: Table 3: [DGH2001] JHHMMSS.ss+DDMMSS.s N=3. Tables A1, A2: [DGH2001] Name N (Nos 1-7).
Simbad objects: 17
To bookmark this query, right click on this link: simbad:2001MNRAS.326.1076D and select 'bookmark this link' or equivalent in the popup menu