2003ApJ...586L..53O

Background observations obtained with the Far Ultraviolet Spectroscopic Explorer toward l=95°.4, b=36°.1 show O VI λλ1032, 1038 in emission. This sight line probes a region of stronger than average soft X-ray emission in the direction of high-velocity cloud Complex C above a part of the disk in which Hα filaments rise into the halo. The O VI intensities, 1600±300 photons.s^–1.cm^–2.sr^–1 (1032 Å) and 800±300 photons.s^–1.cm^–2.sr^–1 (1038 Å), are the lowest detected in emission in the Milky Way to date. A second sight line nearby (l=99°.3, b=43°.3) also shows O VI λ1032 emission but with too low a signal-to-noise ratio to obtain reliable measurements. The measured intensities, velocities, and FWHMs of the O VI doublet and the C II* line at 1037 Å are consistent with a model in which the observed emission is produced in the Galactic halo by hot gas ejected by supernovae in the Perseus arm. An association of the observed gas with Complex C appears unlikely.