Hubble Space Telescope Photometry of Clusters of Galaxies behind the Dwarf Irregular Galaxies DDO 216 and IC 1613 and the Small Magellanic Cloud

摘要

We have measured the integrated colors of galaxies in clusters located behind the dwarf irregular galaxies DDO 216 (Pegasus) and IC 1613 and a position in the Small Magellanic Cloud (SMC) near the cluster Lindsey 31. We examine limits on the accuracy of using these for studying the total extinction in galaxies. We show that the method is feasible if the data include images through three filters, the distant galaxies are in a cluster (all at nearly the same redshift), the reshift is measured for K-correction, and the cluster has an adequate number of type E/S0 galaxies. It is also beneficial if the cluster extends to late-type galaxies and has sufficient resolution for adequate morphological classification. For DDO 216 and IC 1613, the fit obtained shows no significant reddening, while for the SMC near Lindsey 31 the data are limited, but they show measurable reddening.