On the Primordial Helium Abundance and the DeltaY/DeltaO Ratio

M. Peimbert; V. Luridiana; A. Peimbert; L. Carigi

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On the Primordial Helium Abundance and the DeltaY/DeltaO Ratio

M. Peimbert·V. Luridiana·A. Peimbert·L. Carigi

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Abstract

We present a review on the determination of the primordial helium abundance, Yp, based on the study of hydrogen and helium recombination lines in extragalactic H II regions. We also discuss the observational determinations of the increase of helium to the increase of oxygen by mass Delta Y/Delta O, and compare them with predictions based on models of galactic chemical evolution.

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M. Peimbert, V. Luridiana, A. Peimbert, L. Carigi. 2007-01-25. On the Primordial Helium Abundance and the DeltaY/DeltaO Ratio. https://arxiv.org/abs/astro-ph/0701313

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