Fig. 4.
Periodogram power of the inspected periods as a function of the number of observations. The most significant period (the reddest one) at 15.5 d is clearly visible with a high power for Nobs > 80, as well as a period around 3 d with a moderate Scargle power, which increases for Nobs > 160 and then decreases again as well as a period between 40 and 50 d.
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