Temperature Scale and Iron Abundances of Very Hot Central Stars of Planetary Nebulae (invited review)

  title={Temperature Scale and Iron Abundances of Very Hot Central Stars of Planetary Nebulae (invited review)},
  author={Klaus Werner and Jochen L. Deetjen and Stefan Dreizler and T Rauch and Jeffrey W. Kruk},
The determination of effective temperatures of very hot central stars (Teff>70000K) by model atmosphere analyses of optical H and He line profiles is afflicted with considerable uncertainty, primarily due to the lack of neutral helium lines. Ionization balances of metals, accessible only with UV lines, allow more precise temperature estimates. The potential of iron lines is pointed out. At the same time iron and other metal abundances, hardly investigated until today, may be derived from UV… 

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