PDFs used to obtain a certain normalized power at a given period for 1 GV protons (left). The auto correlation coefficient for this figure is α = 0.89. The dotted red line marks the uncorrected confidence level CL_uncorr of 95 %. Overall, 5 % of all power values exceed the CL_uncorr at a given period . The dashed red line marks a CL_uncorr of 99.83 %. This confidence level is only exceeded by 5 % of all periodograms at any period. Right: The relation between corrected and uncorrected CL is shown. The dotted and dashed red lines mark a CL_uncorr of 95 %, which corresponds to a CL_corr of 99.83 %.