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Variable Star Candidates in an ACS Field of M31

Benjamin F. Williams
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Abstract

A search for variable stars is performed using two epochs of Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) imaging data for a 9.28 square arcminute portion of M31. This data set reveals 254 sources that vary by at least 4-sigma between epochs. The positions and 2-epoch B-band (equivalent) photometry of these sources are presented. The photometry suggests that this catalog includes most of the RR Lyrae population of this portion of M31.

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Benjamin F. Williams. 2005-02-15. Variable Star Candidates in an ACS Field of M31. https://doi.org/10.1086/429735

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