Upper limits on O VI emission fromVoyager observations
نویسندگان
چکیده
منابع مشابه
Fuse Observations of Nebular O Vi Emission from Ngc 6543 ∗
NGC6543 is one of the few planetary nebulae (PNe) whose X-ray emission has been shown to be extended and originate from hot interior gas. Using FUSE observations we have now detected nebular O VI emission from NGC6543. Its central star, with an effective temperature of ∼50,000 K, is too cool to photoionize O V, so the O VI ions must have been produced by thermal collisions at the interface betw...
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ژورنال
عنوان ژورنال: Journal of Astrophysics and Astronomy
سال: 2002
ISSN: 0250-6335,0973-7758
DOI: 10.1007/bf02702460