Issue |
Astron. Astrophys. Suppl. Ser.
Volume 120, Number 2, December I 1996
|
|
---|---|---|
Page(s) | 207 - 228 | |
DOI | https://doi.org/10.1051/aas:1996289 | |
Published online | 15 December 1996 |
Optical structure and star formation in blue compact dwarf galaxies. I. Observations and profile decomposition
1
Universitäts-Sternwarte, Geismarlandstraße 11, D–37083 Göttingen, Germany
2
deceased August 5, 1993
3
Visiting Astronomer at Kitt Peak National Observatory (KPNO), which is operated by AURA, Inc., under contract with the National Science Foundation
4
Astronomy Department, University of Virginia, P.O. Box 3818, University Station, Charlottesville, VA 22903, U.S.A.
Corresponding author: Send offprint request to: e-amil: papade@usw008.dnet.gwdg.de
Received:
18
December
1995
Accepted:
16
April
1996
We present new B and R CCD surface photometry for a sample of 4 Blue Compact Dwarf Galaxies (BCDs) and 2 higher luminosity starburst galaxies. We find that the BCD surface brightness profiles (SBPs) can be generally well fitted by the sum of the light of 3 distinct components: 1) an exponential component at large radii, with or without a central flattening which describes the underlying older stellar population; 2) a plateau component at intermediate radii and 3) a gaussian component at small radii. The last 2 components describe the ongoing starburst superimposed on the older stellar component. We apply the 3–component decomposition scheme to 8 more BCDs from the literature and, for the total sample of 14 galaxies, derive structural properties such as central surface brightness and scale length, and perform a deprojection to obtain the luminosity density distribution for each component. We also derive color profiles and find that BCDs show generally a reddening outwards, followed by a blueing beyond a transition radius.
Key words: galaxies: compact; photometry; structure; fundamental parameters
© European Southern Observatory (ESO), 1996