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arXiv · astro-ph/0508339

Fluorine abundances in planetary nebulae

Y. Zhang·X-W. Liu
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Abstract

We have determined fluorine abundances from the F II 4789 and F IV 4060 nebular emission lines for a sample of planetary nebulae (PNe). Our results show that fluorine is generally overabundant in PNe, thus providing new evidence for the synthesis of fluorine in asymptotic giant branch (AGB) stars. [F/O] is found to be positively correlated with the C/O abundance ratio, in agreement with the predictions of theoretical models of fluorine production in thermally pulsing AGB stars. A large enhancement of fluorine is observed in the Wolf-Rayet PN NGC 40, suggesting that high mass-loss rates probably favor the survival of fluorine.

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Y. Zhang, X-W. Liu. 2005-08-15. Fluorine abundances in planetary nebulae. https://doi.org/10.1086/497113

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