Representative provider AP1 exploratory periodograms and their empirical global-significance tests. The upper panels show periodogram power as a function of trial period, in hours, for the FFI (left) and fast (right) products after segment-wise detrending and image-vetted masking. Vertical markers label the recurrent candidate clusters near 7.31, 8.87, and 12.72 hr, together with the 17.83 hr doubled-period interpretation of the 8.87 hr feature. The lower panels show the distributions of the largest periodogram power found anywhere in the 1–48 hr range in 1000 OU noise simulations and 1000 MBB realizations. The vertical line marks the maximum power measured in the corresponding observed light curve. A candidate is considered significant only when its observed power is unusual relative to the relevant null distribution and it satisfies the additional cross-product robustness requirements.