Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-06-29
Astronomy and Astrophysics
Astrophysics
Accepted for publication in the Astrophysical Journal Letter
Scientific paper
10.1086/323025
A primary goal of the FUSE mission is to understand the origin of the O VI ion in the interstellar medium of the Galaxy and the Magellanic Clouds. Along sightlines to OB-type stars, these interstellar components are usually blended with O VI stellar wind profiles, which frequently vary in shape. In order to assess the effects of this time-dependent blending on measurements of the interstellar O VI lines, we have undertaken a mini-survey of repeated observations toward OB-type stars in the Galaxy and the Large Magellanic Cloud. These sparse time series, which consist of 2-3 observations separated by intervals ranging from a few days to several months, show that wind variability occurs commonly in O VI (about 60% of a sample of 50 stars), as indeed it does in other resonance lines. However, in the interstellar O VI $\lambda$1032 region, the O VI $\lambda$1038 wind varies only in $\sim$30% of the cases. By examining cases exhibiting large amplitude variations, we conclude that stellar-wind variability {\em generally} introduces negligible uncertainty for single interstellar O VI components along Galactic lines of sight, but can result in substantial errors in measurements of broader components or blends of components like those typically observed toward stars in the Large Magellanic Cloud. Due to possible contamination by discrete absorption components in the stellar O VI line, stars with terminal velocities greater than or equal to the doublet separation (1654 km/s) should be treated with care.
Fullerton Alex W.
Jenkins Edward B.
Lehner Nicholas
Massa Derck L.
Sembach Kenneth Russell
No associations
LandOfFree
The Influence of Stellar Wind Variability on Measurements of Interstellar O VI Along Sightlines to Early-Type Stars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Influence of Stellar Wind Variability on Measurements of Interstellar O VI Along Sightlines to Early-Type Stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Influence of Stellar Wind Variability on Measurements of Interstellar O VI Along Sightlines to Early-Type Stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-330941