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arXiv · 2311.07525

CCD Photometry of the Globular Cluster NGC 5897

A. Ruelas-Mayorga·L. J. Sánchez·E. Macías-Estrada·A. Nigoche-Netro
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Abstract

We report CCD photometric observations of the globular cluster NGC 5897, in the Johnson system filters B, V , R, and I. With the values for these magnitudes we obtain various colour indices and produce several colour-magnitude diagrams. We present eight colour-magnitude diagrams: V vs B-V , B vs B-V , V vs V-I, I vs V-I, R vs R-I, I vs R-I, V vs V-R, and R vs V-R. In all of these diagrams we can clearly see the Giant Branch, the Horizontal Branch and the beginning of the Main Sequence. To the left of the Main Sequence turn-off point we detect a somewhat large number of Blue Straggler stars. We determine the mean value of the visual magnitude of the HB as $16.60 \pm 0.46$. This value is fainter than the value found by other authors.

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A. Ruelas-Mayorga, L. J. Sánchez, E. Macías-Estrada, A. Nigoche-Netro. 2023-11-13. CCD Photometry of the Globular Cluster NGC 5897. https://arxiv.org/abs/2311.07525

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