Astronomy and Astrophysics – Astronomy
Scientific paper
Dec 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005aas...207.6205g&link_type=abstract
American Astronomical Society Meeting 207, #62.05; Bulletin of the American Astronomical Society, Vol. 37, p.1245
Astronomy and Astrophysics
Astronomy
Scientific paper
It is an observational fact that bulges of spiral galaxies contain a high fraction of old and metal-rich stars. Following this observational fact, we have investigated the colors of 21 bulges hosted by a selected sample of high surface brightness spirals and low surface brightness galaxies observed in B and R optical bands and in J and Ks near-IR bands. Using structural parameters derived from these observations we obtain evidence that bulges could be formed by pure disk evolution (secular evolution), in agreement with the suggestion by some authors. The color profiles, especially the near-IR ones show null or almost null color gradients, supporting the hypothesis that the disk stellar populations are similar to that present in the bulge and/or the bulge is in fact a disk with enhanced stellar density (or a pseudobulge). In the optical, half of the galaxies present an inverse color gradient, giving additional evidence in favor of secular evolution for the sample investigated. The comparison of the observed colors with those obtained from spectrophotometric models of galaxy evolution indicate that bulges of the selected sample have solar and subsolar metallicity, and are independent of the current stellar formation rate. Also, we obtain that galaxies hosting small bulges are systematically metal poor compared to those with larger bulges. These results are being checked more carefully with high S/N spectroscopy.
Donzelli Carlos
Galaz Gaspar
Infante Leopoldo
Villalobos A.
No associations
LandOfFree
Bulge evolution in spirals and low surface brightness galaxies 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 Bulge evolution in spirals and low surface brightness galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bulge evolution in spirals and low surface brightness galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1279891