Observations of O VI Emission from the Diffuse Interstellar Medium toward l = 113°, b = 71°
Abstract
Emission from O VI (λλ1032, 1038) in the diffuse interstellar medium was observed in two, long Far Ultraviolet Spectroscopic Explorer (FUSE) observations at l~=113.0d and b~=70.7d (near the quasar HS 1307+4617). The observed intensities are 2580+/-380 (random) +/-360 (systematic) and 1100+/-160 (random) +/-160 (systematic) photons cm-2 s-1 sr-1 in the 1032 and 1038 Å emission lines, respectively. The electron density, thermal pressure, and depth of the emitting gas are calculated from the observed intensities. The velocity of the emitting material is about +10 km s-1 relative to the local standard of rest and less than +30 km s-1 relative to the H I along the line of sight. The similarity suggests that the highly ionized gas is quiescent and not recently shock heated. Emission from the C II 3 s2 S1/2 to 2p2 P3/2 transition at 1037 Å is also observed, and upper limits are placed on the intensities of ultraviolet line emission from C I, C III, N I, N II, Mg II, Si II, S II, S III, S IV, S VI, Fe II, and Fe III.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2002
- DOI:
- 10.1086/339263
- Bibcode:
- 2002ApJ...569..758S
- Keywords:
-
- Galaxy: General;
- Galaxy: Halo;
- ISM: General;
- ISM: Individual: Name: Local Bubble;
- Ultraviolet: ISM