Fluorine Abundance Variations in Red Giants of the Globular Cluster M4 and Early-Cluster Chemical Pollution
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چکیده
We present fluorine abundances in seven red-giant members of the globular cluster M4 (NGC 6121). These abundances were derived from the HF (1–0) R9 line at 2.3357μm in high-resolution infrared spectra obtained with the Phoenix spectrograph on Gemini-South. Many abundances in the target stars have been studied previously, so that their overall abundance distributions are well-mapped. The abundance of fluorine is found to vary by more than a factor of 6, with the F variations being correlated with the already established oxygen variations, and anti-correlated with the sodium and aluminium variations. In this paper
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تاریخ انتشار 2005