The Missing Satellites of the Magellanic Clouds? Gaia Proper Motions of the Recently Discovered Ultra-faint Galaxies

@article{Kallivayalil2018TheMS,  title={The Missing Satellites of the Magellanic Clouds? Gaia Proper Motions of the Recently Discovered Ultra-faint Galaxies},  author={Nitya Kallivayalil and Laura V. Sales and Paul Zivick and Tobias K. Fritz and Andr{\'e}s del Pino and Sangmo Tony Sohn and Gurtina Besla and Roeland P. van der Marel and Julio F. Navarro and Elena Sacchi},  journal={The Astrophysical Journal},  year={2018},  volume={867},  url={https://api.semanticscholar.org/CorpusID:55073922}}
According to LCDM theory, hierarchical evolution occurs on all mass scales, implying that satellites of the Milky Way should also have companions. The recent discovery of ultra-faint dwarf galaxy candidates in close proximity to the Magellanic Clouds provides an opportunity to test this theory. We present proper motion (PM) measurements for 13 of the 32 new dwarf galaxy candidates using Gaia data release 2. All 13 also have radial velocity measurements. We compare the measured 3D velocities of… 

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