The FUSE Survey of OVI Absorption in the Galactic Disk

Abstract

We outline the results from a FUSE Team program designed to characterize OVI absorption in the disk of the Milky Way. We find that OVI absorption occurs throughout most of the Galactic plane, at least out to several kpc from the Sun, and that it is distributed smoothly enough for the column density to decline with height above the disk and with distance in the plane. However, the OVI absorbing gas is clumpy, and moves at peculiar velocities relative to that expected from Galactic rotation. We conclude that the observed absorption is likely to be a direct indicator of the structures formed when violent, dynamical processes heat the ISM, such as blowout from multiple supernovae events.