Distribution of the log(P_peak) estimates vs. log(T_eff) for the same subset of fast rotating stars with 1 < P < 4 days as processed by other methods in Arkhypov et al. (2015b). The red line shows the linear regression of the lower border set of the log(P_peak) cluster, obtained for the minimum values of P_peak (red crossed squares) defined for the sequential ten intervals of T_eff. The green line shows linear regression of log(P_cyc(log(T_eff))) obtained in Arkhypov et al. (2015b) by other methods. The detection limit zone for P_peak, restricted by the Nyquist frequency (2P)⁻¹ for the considered subset of fast rotators appears outside of the displayed frame.