## 4 Statistics of the Results  
The frequency indicator has been tested on a population of 370 discharges of AUG. The disruptive pulses are 177, from 30303 to 30826 and the not-disruptive pulses are 193, from 30300 to 30824. Figure 7: Plot for the pulse 36112. In blue the estimator in (6) for the frequency of the modes. Vertical lines stand for the time instances at which the different estimators considered have triggered an alarm and in red the time instance at which the disruption occurred. In dashed blue, the time instance provided by (8), in dashed green the one used in the control room (CR) at AUG to start mitigation actions (at 0.25 V) and in dashed orange the mitigation valve opening trigger (at 0.35 V). An immediate application of (6) according to the rule in (8) deals with the determination of the time instance at which a mode can be considered as locked in the frame of reference of the laboratory. Such estimates have been compared with those provided by indicator based on the two coils system and currently in use at AUG, to test its application for disruption prediction and mitigation. Table 1 provides a comparison between the statistics obtained from the actual triggers working at AUG and (6). Considering the disruptive cases in Table 1, \"detected\" stands for the number of pulses during which a disruption occurred and that, according to the two indicators, has a locked mode. The word \"missed\" instead stands for the fact that a disruption occurred, but the indicators did not detect a locked mode. Finally, \"early\" means a locked mode has been detected, but too soon from the disruption to be considered a relevant cause of it, i.e., at least 1 s in advance. This latter case is actually important for the DISRTRIG25, 35 signals, less for (6) because it is possible that a mode rotates at a frequency close to its locking, but then starts rotating again. The latter category has been studied further to estimate the limits of (6). Results have been summarized in Table 2.  
Table 2 summarize what stated above. The total number of triggered \"early\" assessments has been divided in two categories: those induced by a slowing down mode, that later in the pulse starts spinning again (\"early by actual slowing down and recovery\") and those induced by fluctuations in the measured signals by spurious MHD events, usually huge ELMs (\"early induced by a MHD Instability\"). This latter case, in fact, had to be expected because even if the driving sinusoidal function \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Disruptive Pulses** & \multicolumn{3}{c}{**DISRTRIG25**} & \multicolumn{3}{c}{**Frequency Estimator in (6) Using the Rule in (8)**} \\ \hline  & 0.25 V & 0.35 V & \(Z=-1.96\) & \(Z=-2.5\) & \(Z=-3\) & \(Z=-4\) & \(Z=-5\) \\ \hline
**Detected [\%]** & 86.4\% & 72.88\% & 83.05\% & 90.96\% & 94.35\% & 93.79\% & 93.22\% \\
**Missed [\%]** & 13.56\% & 27.12\% & 0.00\% & 0.00\% & 1.13\% & 2.82\% & 6.21\% \\
**Early (\textless{1s}) [\%]** & 3.95\% & 1.13\% & 16.95\% & 9.04\% & 4.52\% & 3.39\% & 0.56\% \\ \hline
**Not-Disruptive (193)** & \multicolumn{3}{c}{**DISRTRIG25**} & \multicolumn{3}{c}{**Frequency Estimator in (6) using the rule in (8)**} \\ \hline  & 0.25 V & 0.35 V & \(Z=-1.96\) & \(Z=-2.5\) & \(Z=-3\) & \(Z=-4\) & \(Z=-5\) \\ \hline
**No mode locked [\%]** & 91.19\% & 96.89\% & 75.65\% & 81.87\% & 84.46\% & 91.19\% & 94.82\% \\
**Locked but not** & 8.81\% & 3.11\% & 24.35\% & 18.13\% & 15.54\% & 8.81\% & 5.18\% \\
**disruptive [\%]** & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Comparison between the threshold based indicators currently used in control room at AUG and the estimator (6) used for the tracking of the slowing down of the mode. Both studies, regarding the disruptive and the not-disruptive pulses, have been reported.