Quantitative Morphology of the Intermediate-Redshift Galaxy Cluster Abell 2443 from Ground-Based Imaging -- Evidence for a galaxy concentration index correlation with cluster density

摘要

We present broad-band photometry and provide a quantitative analysis of thestructure of galaxies in the inner region of the Abell Cluster 2443 (z~0.1).The galaxy parameters have been derived by fitting a two-component model(Sersic r^{1/n} bulge and exponential disk) to a magnitude-limited sample.Using a new method of analysis which takes into account the effects of seeingon the structural parameters and considers the ellipticity as an activeparameter, we avoid systematic errors arising from assumptions of circularsymmetry. 76% of the sample galaxies were classified with these models, therest were morphologically peculiar. For the spiral galaxies, the relationbetween n and B/D is consistent with the trend observed in nearby field galaxysamples. The Sersic index n (which can be considered as a concentration index)of the elliptical galaxies is correlated with the local surface density of thecluster. Monte Carlo simulations were used to check the reliability of themethod and determine the magnitude selection criteria.