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Upper limits on O VI Emission From Voyager

Jayant Murthy·R. C. Henry·R. L. Shelton·J. B. Holberg
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Abstract

We have examined 426 {\it Voyager} fields distributed across the sky for \ion{O}{6} ($λλ$ 1032/1038 Å) emission from the Galactic diffuse interstellar medium. No such emission was detected in any of our observed fields. Our most constraining limit was a 90% confidence upper limit of 2600 \phunit on the doublet emission in the direction (l, b) = (117\fdegree3, 50\fdegree6). Combining this with an absorption line measurement in nearly the same direction allows us to place an upper limit of 0.01 cm$^{-3}$ on the electron density of the hot gas in this direction. We have placed 90% confidence upper limits of less than or equal to 10,000 \phunit on the \ion{O}{6} emission in 16 of our 426 observations.

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Jayant Murthy, R. C. Henry, R. L. Shelton, J. B. Holberg. 2001-06-27. Upper limits on O VI Emission From Voyager. https://doi.org/10.1086/323041

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