Probing the lagging halo of the Milky Way

All spiral galaxies rotate.  The Milky Way is no exception.  We know from careful measurements of the velocity of atomic hydrogen gas in the Milky Way that the disk of the galaxy rotates at about 220 km/s.  As we move off the galaxy's midplane the gas appears to slow down in its rotation, lagging behind the rotation of the disk.  There have been conflicting studies about just how quickly the halo begins to lag. These measurements have important implications for understanding the distribution of dark matter in the Milky Way and how the Milky Way acquires new gas.

In this project you will work with the new HI4PI survey of atomic hydrogen in the Milky Way to measure the Milky Way's lagging halo at high precision throughout the galaxy. No prior experience with astronomical data is required, but experience with python would be beneficial.