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A Survey for Low Surface Brightness Dwarf Galaxies Around M31

Taft E. Armandroff·James E. Davies·George H. Jacoby
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Abstract

By applying a digital filtering technique to 1550 square degrees of the POSS-II in the vicinity of M31, we found two previously unidentified very low surface brightness dwarf galaxies which we designate And V and VI. Follow-up imaging with the KPNO 4-m telescope resolved these into stars easily. The V- and I- band images of And V indicate a distance similar to that of M31, and <[Fe/H]> approximately -1.5. All evidence strongly supports its classification as a dwarf spheroidal companion to M31. Data for And VI are being analyzed, but preliminary indications support a similar conclusion. Our search for more dwarfs, including follow-up observations of numerous candidates found via digital filtering, is incomplete; thus, further identifications may be forthcoming.

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Taft E. Armandroff, James E. Davies, George H. Jacoby. 1998-10-20. A Survey for Low Surface Brightness Dwarf Galaxies Around M31. https://arxiv.org/abs/astro-ph/9810299

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