As discussed in klog32628, we can see some breathing of the sensitivity around 60 - 100 Hz in current sensitivity.
That frequently occurred before the lock loss.
We discussed, and we suspected the DAC output of ETMX MN coil. If its value became large due to the tidal effect, the sensitivity became bad due to unknown reason.
As shown in Fig.1., there seems the some correlation between DAC output(H) and trend of the BNS range.
In this morning, Ushiba-san turned on the roll off filter to treat the tidal effect using IP control, then this breathing seemed disappeared, I think.
