Morphological Classification of Galaxies using Photometric Parameters: the Concentration index versus the Coarseness parameter
Abstract
We devise improved photometric parameters for the morphological classification of galaxies using a bright sample from the First Data Release of the Sloan Digital Sky Survey. In addition to using an elliptical aperture concentration index for classification, we introduce a new texture parameter, coarseness, which quantifies deviations from smooth galaxy isophotes. The elliptical aperture concentration index produces morphological classifications that are in appreciably better agreement with visual classifications than those based on circular apertures. With the addition of the coarseness parameter,the success rate of classifying galaxies into early and late types increases to \~88% with respect to the reference visual classification. A reasonably high success rate ~68% is also attained in classifying galaxies into three types, early-type galaxies (E+S0), early- (Sa+Sb) and late- (Sc+Sdm+Im) type spiral galaxies.
Keywords
Cite
@article{arxiv.astro-ph/0507060,
title = {Morphological Classification of Galaxies using Photometric Parameters: the Concentration index versus the Coarseness parameter},
author = {Chisato Yamauchi and Shin-ichi Ichikawa and Mamoru Doi and Naoki Yasuda and Masafumi Yagi and Masataka Fukugita and Sadanori Okamura and Osamu Nakamura and Maki Sekiguchi and Tomotsugu Goto},
journal= {arXiv preprint arXiv:astro-ph/0507060},
year = {2008}
}
Comments
13 pages, 16 figures, accepted by the Astronomical Journal