2002/02/12 by J. Christopher Howk, Blair D. Savage, Howk, J. Christopher +5
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysics (astro-ph) #Astrophysics and Star Formation Studies #Atmospheric Ozone and Climate #FOS: Physical sciences #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0202239
To appear in The Astrophysical Journal. 24 pages including 9 figures and 3 tables
arxiv created 2002/02/12 · openalex publication_date 2002/02/12 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report Far Ultraviolet Spectroscopic Explorer (FUSE) observations of interstellar O VI absorption in the halo of the Milky Way towards 12 early-type stars in the Large Magellanic Cloud (LMC) and 11 in the Small Magellanic Cloud (SMC). The mean column densities of O VI associated with the Galactic halo towards the LMC and SMC are log = 14.52(+0.10,-0.14) and 14.13(+0.14,-0.20), respectively, where the uncertainties represent the standard deviations of the individual measurements about the means. Significant variations in the O VI column densities are observed over all of the angular scales probed by our observations: 0.5-5.0 degrees towards the LMC and 0.05-3.3 degrees towards the SMC. The maximum factors by which the O VI varies between sight lines towards the LMC and SMC are ~2.8 and ~4.2, respectively. Though low-, intermediate-, and high-velocity clouds are present along most of the sight lines towards the LMC, the variations in O VI column densities are found in all of these O VI absorbing structures. The column density variations trace the structure of the hot ionized medium in the Galactic halo on scales of <<80 to 800 pc towards the LMC and <<6 to 400 pc towards the SMC (assuming the absorption arises within the first 5 kpc above the Galactic plane).