Dynamics in the satellite system of Triangulum: Is AndXXII a dwarf satellite of M33?

Understand

We present results from a spectroscopic survey of the dwarf spheroidal And XXII and the two extended clusters EC1 and EC2.

• These three objects are candidate satellites of the Triangulum galaxy, M33, which itself is likely a satellite of M31.
• We use the DEep Imaging Multi-Object Spectrograph mounted on the Keck-II telescope to derive radial velocities for candidate member stars of these objects and thereby identify the stars that are most likely actual members.
• Eleven most probable stellar members (of 13 candidates) are found for AndXXII.