Structural Properties of Early-Type Galaxies from the SDSS DR2

Abstract

Two-dimensional bulge/disk light decomposition with GIM2D inboth the r- and g-bands has been applied to a sample of 129 early-type galaxies brighter than 13.5 magnitude in the r-band, selected from the Sloan Digital Sky Survey Data Release 2. Intensity-weighted Fourier coefficienta4/awas also derived for each sample galaxy. Our analysis shows that there are correlations between bulge-to-total light ratio (B/T) with bulge Sersic index n B and between bulge and disk scale sizes. Isophotal shape parametera 4/ais not correlated with B/T and nB. Both bulge and disk components satisfy a color-magnitude relation. The κ space Fundamental Plane analysis shows that galaxies with larger B/T tend to lie tighter and closer to the line of κ1 + κ2 =8 (the so-called "zone of avoidance") than the galaxies with smaller B/T. It indicates that existence of the disk component may lead to scatter of the distribution on the Fundamental Plane. Our analysis also shows that κ 1 + κ2 correlates with (g-r) color and B/T, but does not correlate witha 4/afor early-type galaxies. The fitted parameters and other retrieved parameters used in this paper for all sample galaxies are available online.