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arXiv · 2012.03904

Updated proper motions for Local Group dwarf galaxies using Gaia Early Data Release 3

Alan W. McConnachie·Kim A. Venn
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Abstract

Updated systemic proper motion estimates for 58 Milky Way satellite galaxies, based on Gaia Early Data Release 3 (EDR3), are provided. This sample is identical to that studied by McConnachie & Venn (2020) and the methodology is essentially unchanged from the original paper. The superiority of Gaia EDR3 compared to Gaia Data Release 2 means that Bo{\"o}tes 4, Cetus 3, Pegasus 3 and Virgo 1 have detectable systemic proper motions for the first time. For the entire galaxy sample, the median random uncertainties in the systemic proper motions are approximately a factor of two better than the previous estimates using Gaia DR2. Relevant systematic errors, which are also a factor of two smaller, dominate over random uncertainties for 25 out of the 58 objects in the sample.

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Alan W. McConnachie, Kim A. Venn. 2020-12-07. Updated proper motions for Local Group dwarf galaxies using Gaia Early Data Release 3. https://arxiv.org/abs/2012.03904

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