Abstract
Photographic intermediate banduvb observations of RGB and some AGB stars in 7 × 7 arcmin fields centered on the globular clusters M 15 and NGC 6712 are obtained. The photometric data is not fully reduced to the standard system but it is converted in an unique instrumental system. The photometry confirms the existence of the gaps in the giant branch of M 15. For NGC 6712 the Stromgren colors show a bimodal distribution and point at a bimodal carbon abundance for the bright giants from the central part. The possibilities of theuvby system for a classification of RGB and AGB stars are briefly discussed.
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Kaltcheva, N.T. Photographic UVB photometry of the globular clusters M 15 and NGC 6712. Astrophys Space Sci 206, 103–110 (1993). https://doi.org/10.1007/BF00658386
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DOI: https://doi.org/10.1007/BF00658386