Bulge-Disk Decomposition of 659 Spiral and Lenticular Galaxy Brightness Profiles

Abstract

We present one of the largest homogeneous sets of spiral and lenticular galaxy brightness profile decompositions completed to date. The 659 galaxies in our sample have been fitted with a de Vaucouleurs law for the bulge component and an inner-truncated exponential for the disk component. Of the 659 galaxies in the sample, 620 were successfully fitted with the chosen fitting functions. The fits are generally well defined, with more than 90% having rms deviations from the observed profile of less than 0.35 mag. We find no correlations of fitting quality, as measured by these rms residuals, with either morphological type or inclination. Similarly, the estimated errors of the fitted coefficients show no significant trends with type or inclination. These decompositions form a useful basis for the study of the light distributions of spiral and lenticular galaxies. The object base is sufficiently large that well-defined samples of galaxies can be selected from it.