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The N/O abundance ratio in the lowest-metallicity blue compact dwarf galaxies

Y. Izotov·F. Chaffee·C. Foltz·K. Fricke·R. Green·N. Guseva·K. Noeske·P. Papaderos·T. Thuan
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Abstract

The results of the N/O abundance determination in a sample of low-metallicity blue compact dwarf (BCD) galaxies based on new spectroscopic observations with large telescopes (Keck, VLT, MMT, 4m KPNO) are presented. We show that the N/O abundance ratio is constant at lowest metallicities < Zsun/20, confirming previous findings and strongly supporting the origin of nitrogen as a primary element.

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Y. Izotov, F. Chaffee, C. Foltz, K. Fricke, R. Green, N. Guseva, K. Noeske, P. Papaderos, T. Thuan. 2001-09-27. The N/O abundance ratio in the lowest-metallicity blue compact dwarf galaxies. https://arxiv.org/abs/astro-ph/0109519

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