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arXiv · 2002.06651

Cycles on the Solar-Type Stars and Cooler Dwarfs

N. I. Bondar·M. M. Katsova·M. A. Livshits
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Abstract

Features of the development of activity cycles in the solar-type stars and fast-rotating cool dwarfs have been considered for 65 stars observed in some decades. Cycles with duration of 7-18 years compared to the solar cycle were found for about 50% of the studied stars. In cooler dwarfs with rotation periods of less than 5 days, cyclic changes in brightness occur on longer scales, up to 80 years. Activity of the highest level is produced on K dwarfs; their main cycles are long and have the highest amplitudes. Both old and young solar-type stars show a similar tendency in increasing the cycle length with a slower rotation. No evidence for a relation between the rotation period and duration of cycles was found for cool dwarfs with $P_{rot} < 5$ days.

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N. I. Bondar, M. M. Katsova, M. A. Livshits. 2020-02-16. Cycles on the Solar-Type Stars and Cooler Dwarfs. https://doi.org/10.1134/s0016793219070089

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