Far Ultraviolet Spectroscopic ExplorerObservations of Nebular OviEmission from NGC 6543

Robert A. Gruendl, You-Hua Chu, Martín A. Guerrero
2004 Astrophysical Journal  
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
more » ... al 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.
doi:10.1086/427389 fatcat:3f5aopzn35fgxnfazt3frjnyo4