Wavelet power spectrum for K2 data on RX J1604.3-2130. Left panel: wavelet spectrum in time. Color scale is set between minimum and maximum power, and global significance limits are marked as thick black (95% confidence) and thin black (90% confidence) contours, calculated for a red noise data model with α = 0.98. Regions where edge effects could be significant are masked out. Horizontal lines mark positions of the GLSP peaks found with K2 and REM (at 8.9 d, 5.5 d, 5.0 d, 4.9 d, 2.59 d, 2.39 d). Right panel: global wavelet power together with the significance, the noise spectrum, and the scaled GLSP for comparison.