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FUSE Observations of Nebular O VI Emission from NGC 6543

R. A. Gruendl·Y. -H. Chu·M. A. Guerrero
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Abstract

NGC 6543 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 NGC 6543. 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 between the hot interior gas and the cool nebular shell. We modeled the O VI emission incorporating thermal conduction, but find that simplistic assumptions for the AGB and fast wind mass loss rates overproduce X-ray emission and O VI emission. We have therefore adopted the pressure of the interior hot gas for the interface layer and find that expected O VI emission to be comparable to the observations.

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R. A. Gruendl, Y. -H. Chu, M. A. Guerrero. 2004-11-15. FUSE Observations of Nebular O VI Emission from NGC 6543. https://doi.org/10.1086/427389

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