Solar-type Surface Differential Rotation on a K-dwarf LO Peg
Top panel of the above figure shows the V-band light curve (solid triangles) along with the mean magnitude of each season (open circles). Solid circles in bottom panel shows the derived rotational periods in each season. The highest peak above 90 per cent significance level in the Scargle–Press periodogram of these seasonal periods indicates the cyclic period of 2.7 ± 0.1 yr. In bottom panel each period of 2.7 ± 0.1 yr is indicated with the vertical lines. The straight lines in each cycle show a linear fit to data during the cycle. The rotation period monotonically decreases along most the star-spot cycles showing a solar-like behaviour.
[Image Credit: Karmakar et al. (2016)]