Determination of the escape velocity of the Milky Way using a proper motion selected halo sample

Understand

The {\it Gaia} mission has provided the largest catalogue ever of sources with tangential velocity information.

• However, using this catalogue for dynamical studies is difficult because most of the stars lack line-of-sight velocity measurements.
• Recently, we presented a selection of $\sim 10^7$ halo stars with accurate distances that have been selected based on their photometry and proper motions.
• Using this sample, we model the tail of the velocity distribution with a power-law distribution, a commonly used approach first established by \cite{Leonard1990THESPEED}.