Recent FUSE Observations of Diffuse O VI Emission from the Interstellar Medium

W. Van Dyke Dixon; Ravi Sankrit

doi:10.1063/1.3154025

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arXiv · 0807.1237

Recent FUSE Observations of Diffuse O VI Emission from the Interstellar Medium

W. Van Dyke Dixon·Ravi Sankrit

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Abstract

We present new results from our survey of diffuse O VI-emitting gas in the interstellar medium with the Far Ultraviolet Spectroscopic Explorer (FUSE). Background observations obtained since 2005 have yielded eleven new O VI detections of 3-sigma significance, and archival searches have revealed two more. An additional 15 sight lines yield interesting upper limits. Combined with previous results, these observations reveal the large-scale structure of the O VI-bearing gas in the quadrant of the sky centered on the Magellanic Clouds. The most prominent feature is a layer of low-velocity O VI emission extending more than 70 degrees from the Galactic plane. At low latitudes (|b| < 30 degrees), the emission comes from narrow, high-density conductive interfaces in the local ISM. At high latitudes, the emission is from extended, low-density regions in the Galactic halo. We also detect O VI emission from the interface region of the Magellanic System, a structure recently identified from H I observations. These are the first detections of emission from high-ionization species in the Magellanic System outside of the Clouds themselves.

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W. Van Dyke Dixon, Ravi Sankrit. 2008-07-08. Recent FUSE Observations of Diffuse O VI Emission from the Interstellar Medium. https://doi.org/10.1063/1.3154025

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