Kinematics of Antlia 2 and Crater 2 from the Southern Stellar Stream Spectroscopic Survey (S 5)

@article{Ji2021KinematicsOA,  title={Kinematics of Antlia 2 and Crater 2 from the Southern Stellar Stream Spectroscopic Survey (S 5)},  author={Alexander P. Ji and Sergey E. Koposov and Ting S. Li and Denis Erkal and Andrew B. Pace and Joshua D. Simon and Vasily A Belokurov and Lara R. Cullinane and Gary Da Costa and Kyler W. Kuehn and Geraint F. Lewis and Dougal Mackey and Nora Shipp and Jeffrey D. Simpson and Daniel B. Zucker and Terese T. Hansen and Joss Bland-Hawthorn and Sdss Collaboration},  journal={The Astrophysical Journal},  year={2021},  volume={921},  url={https://api.semanticscholar.org/CorpusID:235624056}}
We present new spectroscopic observations of the diffuse Milky Way satellite galaxies Antlia 2 and Crater 2, taken as part of the Southern Stellar Stream Spectroscopic Survey (S 5). The new observations approximately double the number of confirmed member stars in each galaxy and more than double the spatial extent of spectroscopic observations in Antlia 2. A full kinematic analysis, including Gaia EDR3 proper motions, detects a clear velocity gradient in Antlia 2 and a tentative velocity… 

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