The Resolved Outer Population of NGC 6822 with WFPC2

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Abstract
We present F336W (U), F439W (B), F555W (V), and F675W (R) Wide Field Planetary Camera 2 (WFPC2) photometry of two outer regions of the Local Group dwarf irregular galaxy NGC 6822. The northeast region is ~13' from the galaxy center, whereas the west region lies 10' out and within the wispy low surface brightness outer regions of the galaxy. The fields are not crowded and contain few NGC 6822 stars. We discuss the errors and uncertainties and find that the west region contains a main sequence that extends to stars of about 2 M⊙, with an age of about 200 Myr. The northeast region has no main sequence or stars younger than 1 Gyr but does contain some luminous red stars that are not matched in the west field. These stars are not clumped in the field. The results suggest that the west region may be a trace of a tidal event that triggered the current star formation in this isolated galaxy.
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