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arXiv · 2208.06190

Solar and stellar activity cycles -- no synchronization with exoplanets

V. N. Obridko·M. M. Katsova·D. D. Sokoloff
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Abstract

Cyclic activity on the Sun and stars is primarily explained by generation of the magnetic field by a dynamo mechanism, which converts the energy of the poloidal field into the energy of the toroidal component due to differential rotation. There is, however, an alternative point of view, which explains the field generation by gravitational influence of the planetary system and, first of all, Jupiter. This hypothesis can be verified by comparing the characteristics of exoplanets with the activity variations on their associated stars. We have performed such a comparison and have drawn a negative conclusion. No relationship between the gravitational influence of the exoplanets and cycle of the host star could be found in any of the cases considered. Moreover, there are reasons to believe that a strong gravitational influence may completely eliminate cyclic variation in stellar activity.

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V. N. Obridko, M. M. Katsova, D. D. Sokoloff. 2022-08-12. Solar and stellar activity cycles -- no synchronization with exoplanets. https://doi.org/10.1093/mnras%2Fstac2286

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