ar X iv : a st ro - p h / 01 05 21 4 v 1 1 4 M ay 2 00 1 Upper limits on O VI Emission From Voyager Observations
نویسنده
چکیده
We have examined 426 Voyager fields distributed across the sky for O VI (λλ 1032/1038Å) 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 photons cm −2 sr −1 s −1 on the doublet emission in the direction (l, b) = (117. • 3, 50. • 6). 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 photons cm −2 sr −1 s −1 on the O VI emission in 16 of our 426 observations.
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ar X iv : a st ro - p h / 01 05 21 4 v 2 2 7 Ju n 20 01 Upper limits on O VI Emission From Voyager Observations
We have examined 426 Voyager fields distributed across the sky for O VI (λλ 1032/1038Å) 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 photons cm −2 sr −1 s −1 on the doublet emission in the direction (l, b) = (117.3, 50.6). Combining this with an absorption...
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