The Dependence of Stellar Activity Cycles on Effective Temperature

نویسندگان

چکیده

This paper proposes the idea that observed dependence of stellar activity cycles on rotation rate can be a manifestation stronger effective temperature. Observational evidence is recalled and theoretical arguments are given for presence cyclic in case sufficiently slow only. Slow means proximity to upper bound period solar-type stars. maximum depends temperature shortens hotter The interpreted as minimum operation large-scale dynamo. A combined model differential dynamo applied stars different mass rotating with slightly above threshold Computations show shorter As rotate faster, computed also faster rotation. smaller explained by larger amplitude $\alpha$-effect onset their dynamos: $\alpha$ demands (cycling) magnetic energy computations proportional difference between its Stars moderately rates differ significantly super-criticality dynamos therefore activity, observed.

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ژورنال

عنوان ژورنال: Research in Astronomy and Astrophysics

سال: 2022

ISSN: ['1674-4527', '2397-6209']

DOI: https://doi.org/10.1088/1674-4527/ac9780