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Measuring Chemical Abundances in Extragalactic Metal-Rich HII Regions

Fabio Bresolin
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Abstract

The analysis of metal-rich HII regions has a profound impact on the calibration of abundance diagnostics widely used to measure the chemical content of star-forming galaxies, both locally and at high redshift. I review the main difficulties that affect direct abundance determinations from temperature-sensitive collisionally excited lines, and briefly discuss strong-line methods, in particular their empirical calibration. In the near future it will be possible to calibrate strong-line methods using metal recombination lines, providing abundances that are virtually insensitive to uncertainties on the nebular temperature structure.

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Fabio Bresolin. 2006-08-19. Measuring Chemical Abundances in Extragalactic Metal-Rich HII Regions. https://arxiv.org/abs/astro-ph/0608410

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