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arXiv · 2111.05911

Activity cycles in RS CVn type stars

C. I. Martínez·P. J. D. Mauas·A. P. Buccino
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Abstract

We compile a list of 121 RS CVn type stars from the bibliography in southern hemisphere, to search for activity cycles, covering a large range of luminosities and rotation periods. For each system of the list, we obtain photometric data from the All Sky Automated Survey (ASAS), and we complement it with our own photometry, obtained with the Optical Robotic Observatory (ORO). We analyze this data with the Generalized Lomb-Scargle periodogram to determine the rotation period and possible activity cycles for each system. We found rotation periods for 102 systems and activity cycles for 91 systems. From the statistical analysis of the results, we found that giant stars behave differently than subgiants and main-sequence stars, and that there is a good correlation between rotation periods and luminosities.

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C. I. Martínez, P. J. D. Mauas, A. P. Buccino. 2021-11-10. Activity cycles in RS CVn type stars. https://doi.org/10.1093/mnras%2Fstac755

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