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arXiv · 1608.01549

New Suns in the Cosmos II: Differential rotation in Kepler Sun-like stars

M. L. Das Chagas·J. P. Bravo·A. D. Costa·C. E. Ferreira Lopes·R. Silva Sobrinho·F. Paz-Chinchón·I. C. Leão·A. Valio·D. B. de Freitas·B. L. Canto Martins·A. F. Lanza·J. R. De Medeiros
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Abstract

The present study reports the discovery of Sun-like stars, namely main-sequence stars with $T_{\rm eff}$, $\log g$ and rotation periods $P_{rot}$ similar to solar values, presenting evidence of surface differential rotation. An autocorrelation of the time series was used to select stars presenting photometric signal stability from a sample of 881 stars with light curves collected by the $Kepler$ space-borne telescope, in which we have identified 17 stars with stable signals. A simple two-spot model together with a Bayesian information criterion were applied to these stars in the search for indications of differential rotation; in addition, for all 17 stars, it was possible to compute the spot rotation period $P$, the mean values of the individual spot rotation periods and their respective colatitudes, and the relative amplitude of the differential rotation.

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M. L. Das Chagas, J. P. Bravo, A. D. Costa, C. E. Ferreira Lopes, R. Silva Sobrinho, F. Paz-Chinchón, I. C. Leão, A. Valio, D. B. de Freitas, B. L. Canto Martins, A. F. Lanza, J. R. De Medeiros. 2016-08-10. New Suns in the Cosmos II: Differential rotation in Kepler Sun-like stars. https://doi.org/10.1093/mnras%2Fstw2026

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