Since yesterday we have been struggling to damp ITMY mode 05/06. The nominal settings (with reduced gains) works for some time (as it worked yesterday) and then it turns around and starts getting worse. Hence, I tweaked the settings and found a new one which seems to be working for now (the drive and both the modes have been decreasing for the last few hours),
New settings: FM6+FM8+FM10 Gain -0.02 (phase +30)
I unsuccessfully tried the following two settings which made IY05 worse (while it was working fine for IY06),
FM6+FM10 Gain -0.02 - did not work for IY05, works for IY06 (no phase)
FM6+FM7+FM10 Gain -0.02 - did not work for IY05, works for IY06 (phase -30)
For now I have set the gains to zero on lscparams and would like to test the new settings manually for few locks before committing it in guardian.
I will keep watching the progress for the next few hours.
We were kicked out of Observing for few minutes while I loaded the violin damping guardian. Also LLO was out of Observe at this time so this was a good opportunity to make the changes.
We lost lock in between, however after a new lock was acquired the above setting still looks to be working fine (2hrs and damping down nicely). I will leave it like this overnight and hopefully if we remain locked then IY05/06 should have made good progress.
IY mode 05 and 06 has dropped down by roughly two orders of magnitude since Sat morning - see screenshot attached.
I might try and increase the gain to speed it up.
