Panels (a) and (b): Lomb-Scargle power of the λ₀(ω) (solid blue line) and σ(ω) (solid red line) shown in panels (b), (c), and (e), (f) of Fig. 1. The horizontal dashed cyan lines mark the confidence level of 99% (corresponding to a false-alarm probability of 0.01) for the periodicities. Panels (c) and (d): Periodicity (in units of rad) distributions for the 864 and 894 cases according to the elliptical accretion disk model and the circular accretion disk plus arms model, respectively. The blue and red histograms show the results for the periodicity distributions in λ₀(ω) and σ(ω), respectively. Panels (e) and (f): Distributions of R_fs according to the elliptical accretion disk model and the circular accretion disk plus arms model, respectively.