Presentation #330.05 in the session “The Milky Way and Galactic Center”.
Surrounding the Milky Way (MW) is a region of hot X-ray emitting gas, commonly referred to as the halo or the circumgalactic medium (CGM). The CGM has significant influence on the star formation history and evolution of the MW. Gas likely enters and exits the CGM from both the MW disk and from outside the MW, but the balance of these processes is not known. The HaloSat CubeSat has completed an all-sky survey of soft X-ray emission which is predominately produced by million-degree Kelvin gas in the CGM. A previous study of the HaloSat data mapped the distribution of CGM emission in the southern MW halo (<-30 degrees galactic latitude) and found the emission to be clumpy. This analysis has now been expanded to include the northern MW halo (>30 degrees galactic latitude), which was also found to exhibit a similarly clumpy distribution. This strongly implies that this emission is dominated by gas ejected from the MW disk by feedback processes such as supernovae or OB stars. The HaloSat observations were also analyzed for any evidence of an additional hotter gas component in the CGM.