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

Published 2016-08-04Version 1

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.