This channel indicates an integer number of GPS time measured on each model.
In Fig.1, error and feedback signal on CAL model and feedback signal on ETMX model have gaps.
At the same time, TIME_DIAG channel of CAL model (FEC-11) and ETMX model (FEC-103) shows a decrement of GPS time.
In order to detect this kind of gaps, using TIME_DIAG seems to be the most efficient because they are sampled as 16Hz and they works even signals shows continuous digital zero such as feedback signal in the DOWN state as shown in Fig.2.
Detection condition can be described as
where x(t_i) is K1:FEC-*_TIME_DIAG.
According to this method, event rate in recent one week is ~30gaps/day.
And also most of gaps occurs during 10:00-14:00 JST as shown in Fig.3.
It doesn't seem to depend on the IFO situation (lock or unlock).
This may become a hint about instability of trouble rate.
Though the 1st priority is removing this problem, I'm not sure that it's possible until O4a start.
So I prepared a script (/users/DET/tools/Segments/Script/DAQ_IPC_ERROR.py)
for making segment information as the next best solution for observing runs.
