1. Several reduction around 19:00:00(UTC)
We detected several reduction of the sensitivity around 19:00:00 last night.
I checked the spectrum as shown in Fig.1., some f^-3 line can be detected.
Fig.2. showed the status of the tidal control, no significant reason can be found from tidal effect.
From the Fig.1., I noticed that the one violin peak became larger during this period.
The frequency of peak is 181.875.
From the past check of klog32643, it would be the one resonant peak of the ITMX.
181.9375 NOEYIMP IXIMP 12/06:55:00
If one violin peak excited, the sensitivity became worse?? and what is the effect of the f^-3??
2. Long time lock (more than several hours)
Compared from yesterday, the lock duration became longer last night.
I checked the signals related with ETMY MN oplev(Fig.3).
Actually, number of larger spike like signal were reduced last night.
It is very difficult question we should change the target temperature of the oplev light source at ETMY MN TILT.
Became stable of the environment of ETMY or just a colm phase?
3. Some reduction after the 23:00(UTC)
Maybe construction work started, the sensitivity became worse.
One new things is around the ground peak (300 Hz, 480 Hz, 600 Hz etc.) there are some sideband
