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The Spectra of Main Sequence Stars in Galactic Globular Clusters II. CH and CN Bands in M71

J. G. Cohen
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Abstract

Spectra with a high signal-to-noise ratio of 79 stars which are just below the main sequence turnoff of M71 are presented. They yield indices for the strength of the G band of CH and the ultraviolet CN band at 3885 Å. These indices are each to first order bimodal and they are anti-correlated. There are approximately equal numbers of CN weak/CH strong and CN strong/CH weak main sequence stars in M71. It is not yet clear whether these star-to-star variations arise from primordial variations or from mixing within a fraction of individual stars as they evolve.

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J. G. Cohen. 1999-01-26. The Spectra of Main Sequence Stars in Galactic Globular Clusters II. CH and CN Bands in M71. https://doi.org/10.1086/300860

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