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arXiv · 1006.0692

On the O/H, Mg/H, Si/H and Fe/H Gas and Dust Abundance Ratios in Galactic and Extragalactic H II Regions

Antonio Peimbert·Manuel Peimbert
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Abstract

We derive the Mg/H ratio in the Orion nebula and in 30 Doradus. We also derive the O/H and the Fe/O ratios in the extremely metal poor galaxy SBS 0335-052. We estimate the dust depletions of Mg, Si, and Fe in Galactic and extragalactic H II regions. Based on these depletions we estimate the fraction of O atoms embedded in dust as a function of the O/H ratio. We find an increasing depletion of O with increasing O/H. The O depletion increases from about 0.08 dex, for the metal poorest H II regions known, to about 0.12 dex, for metal rich H II regions. This depletion has to be considered when comparing nebular with stellar abundances.

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Antonio Peimbert, Manuel Peimbert. 2010-06-03. On the O/H, Mg/H, Si/H and Fe/H Gas and Dust Abundance Ratios in Galactic and Extragalactic H II Regions. https://doi.org/10.1088/0004-637x/724/1/791

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