The Structure of the Stellar Hosts in Blue Compact Dwarf Galaxies

Amorín, R. O.; Aguerri, J. A. L.; Cairós, L. M.; Caon, N.; Muñoz-Tuñon, C.
Bibliographical reference

Galaxy Evolution Across the Hubble Time, Edited by F. Combes and J. Palous, Proceedings of the International Astronomical Union 2, IAU Symposium #235, held 14-17 August, 2006 in Prague, Czech Republic. Cambridge: Cambridge University Press, 2007., pp.300-300

Advertised on:
0
2007
Number of authors
5
IAC number of authors
1
Citations
1
Refereed citations
1
Description
The structural parameters of the low surface brightness stellar host in Blue Compact Dwarf galaxies are often studied by fitting R1/n models to the outer regions of their radial profiles. The limitations imposed by the presence of a large starburst emission overlapping the underlying component makes this kind of analysis a difficult task. We propose a two-dimensional fitting methodology in order to improve the extraction of the structural parameters of the LSB host. We discuss its advantages and weaknesses, and compare the results for a sample of eight objects with those already obtained using a one-dimensional technique. We fit a PSF convolved Sérsic model to the BVR images. We restrict the fit to the stellar host by masking out the starburst region and take special care to minimize the sky-subtraction uncertainties. Consistency checks are performed to assess the reliability and accuracy of the derived structural parameters. We obtain robust fits for all the sample galaxies, all of which, except one, show low Sérsic indices n -very close to one-- with good agreement in the three bands. These findings suggest that the stellar hosts in BCDs have near-exponential profiles, a result that will help us to understand the mechanisms that form and shape BCD galaxies, and how they relate to the other dwarf galaxy classes