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arXiv · 1103.3037

An overabundance of oxygen in planetary nebulae of the solar neighborhood

Mónica Rodríguez·Gloria Delgado-Inglada
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Abstract

We study the oxygen abundance in five H II regions and seven planetary nebulae (PNe) located within 2 kpc from the Sun that have available spectra of high quality. Our analysis uses a similar procedure and the same atomic data to derive abundances in all the objects. The results calculated with collisionally excited lines for the H II regions indicate that the local interstellar medium is very homogeneous, with 12+log(O/H)=8.45-8.54. As for the PNe, six out of seven show significantly higher abundances: 12+log(O/H)=8.65-8.80. This overabundance of oxygen in PNe also holds when we consider the abundances implied by recombination lines.

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Mónica Rodríguez, Gloria Delgado-Inglada. 2011-03-15. An overabundance of oxygen in planetary nebulae of the solar neighborhood. https://arxiv.org/abs/1103.3037

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