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Chemical Abundances in our Galaxy and Other Galaxies Derived from H II Regions

M. Peimbert·L. Carigi·A. Peimbert
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Abstract

We discuss the accuracy of the abundance determinations of H II regions in our Galaxy and other galaxies. We focus on the main observational constraints derived from abundance determinations that have implications for models of galactic chemical evolution: a) the helium to hydrogen abundance ratio, He/H; b) the oxygen to hydrogen abundance ratio, O/H; c) the carbon to oxygen abundance ratio, C/O; d) the helium to oxygen and helium to heavy elements abundance ratios, Delta Y/ Delta O and Delta Y/ Delta Z; and e) the primordial helium abundance, Yp.

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M. Peimbert, L. Carigi, A. Peimbert. 2000-07-20. Chemical Abundances in our Galaxy and Other Galaxies Derived from H II Regions. https://doi.org/10.1023/a%3A1012789324221

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