Variability Survey of Southern Open Clusters NGC 6134, NGC 6416, Collinder 394, and Alessi 10

Authors

  • Denny Mandey Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Dhimaz Gilang Ramadhan Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Muhammad Yusuf Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Teduh Perhati Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Sahlan Ramadhan Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Theofilus Hobba Pramono Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Chornelis J?Be Anin Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Premana Wardayanti Premadi Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Anton Timur Jaelani Astronomy Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia
  • Agus Triono Puri Jatmiko Bosscha Observatory, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Lembang 40391, Indonesia
  • Mochamad Ikbal Arifyanto Astronomy Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia

DOI:

https://doi.org/10.5614/j.math.fund.sci.2026.57.3.1

Keywords:

differential photometry, eclipsing binary, exoplanet, southern open cluster, variable star

Abstract

We present the results of a brightness variability survey of four southern open clusters, namely NGC 6134, NGC 6416, Collinder 394, and Alessi 10, which were observed using three telescopes following a time series photometric scheme during the dry season in 2022. The purpose of these observations was to detect variability events and their types of variability in star members of these four clusters. Data analysis was performed using a differential photometry method to produce light curves. Several new variable star candidates were discovered in the observed clusters. More observational data are needed to examine the consistency of the variabilities, estimate relevant periodicity, and determine the type of variable star.

References

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Published

2026-02-28

How to Cite

Mandey, D. ., Ramadhan, D. G. ., Yusuf, M. ., Perhati, T. ., Ramadhan, S., Pramono, T. H. ., Anin, C. J. ., Premadi, P. W. ., Jaelani, A. T. ., Jatmiko, A. T. P. ., & Arifyanto, M. I. . (2026). Variability Survey of Southern Open Clusters NGC 6134, NGC 6416, Collinder 394, and Alessi 10. Journal of Mathematical and Fundamental Sciences, 57(3), 173-183. https://doi.org/10.5614/j.math.fund.sci.2026.57.3.1