Sheila, Stefan, Ryan S

Overnight the IFO re-locked itself 7 times with the guardian changes that Elenna made last night (66244).  Great.  

The locklosses seem to be caused by a soft yaw oscillation, the first two screenshots attached show optical levers and ASC signals for one of these unattended locklosses.  According to the optical levers the problem seems to be csoft yaw.  

While we were looking at these plots this started to ring up again, I tried turning up the csoft yaw gain, which seems from the third attachment like it helped.  I misinterpreted the plots on the wall and turned the gain down to 5; we then lost lock.  According to Elenna's measurement and model this should be stable, 66232.  

We also lost lock due to a similar ring up at the low noise ESD transitions, I've now edited the guardian state POWER_25W to set the CSOFT Y gain to 20, we will see how this lock attempt goes.