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arXiv · 1304.3185

Optical and mid-infrared neon abundance determinations in star-forming regions

Oli L. Dors Jr.·Guillermo F. Hagele·Monica V. Cardaci·Enrique Perez-Montero·Angela C. Krabbe·Jose M. Vilchez·Dinalva A. Sales·Rogerio Riffel·Rogemar A. Riffel
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Abstract

We employed observational spectroscopic data of star-forming regions compiled from the literature and photoionization models to analyse the neon ionic abundances obtained using both optical and mid-infrared emission-lines. Comparing Ne++/H+ ionic abundances from distinct methods, we found that, in average, the abundances obtained via IR emission-lines are higher than those obtained via optical lines by a factor of 4. Photoionization models with abundance variations along the radius of the hypothetical nebula provide a possible explanation for a large part of the difference between ionic abundances via optical and infrared emission-lines. Ionization Correction Factor (ICF) for the neon is obtained from direct determinations of ionic fractions using infrared emission-lines. A constant Ne/O ratio (logNe/O \approx -0.70) for a large range of metallicity, independently of the ICF used to compute the neon total abundance is derived.

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Oli L. Dors Jr., Guillermo F. Hagele, Monica V. Cardaci, Enrique Perez-Montero, Angela C. Krabbe, Jose M. Vilchez, Dinalva A. Sales, Rogerio Riffel, Rogemar A. Riffel. 2013-04-11. Optical and mid-infrared neon abundance determinations in star-forming regions. https://doi.org/10.1093/mnras%2Fstt610

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