HST Color-Magnitude Diagrams of Globular Clusters in NGC 185 and NGC 205

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Abstract
We present a progress report on our ongoing HST WFPC2 study of globular clusters in NGC 185 and NGC 205. Most of the cluster candidates studied previously only from the ground are indeed globular clusters; however, several candidates turn out to be either foreground stars or background galaxies. In addition, we have discovered one new, previously unsuspected cluster. A complete knowledge of the globular cluster systems in even these nearby galaxies requires high spatial resolution data. We then derive preliminary I, (V – I) color-magnitude diagrams for some of the clusters, as well as for their surrounding fields. The clusters show the blue horizontal branches expected for the low metallicities we derive, which are in agreement with those derived from ground-based integrated spectra. The fields appear generally more metal-rich than indicated by previous ground-based studies. The field blue horizontal branch in NGC 185 is only a very minor component, while that in NGC 205 is even smaller. After all of our observations have been acquired, these data will allow a very accurate knowledge of the individual and composite properties of the globular cluster systems of these 2 galaxies, as well as those of their field stars.