02:27 UTC The TCS_ITMY_CO2 guardian node has transitioned to FIND_LOCK_POINT. The number of SDF differences is varying. One instance of them is attached.
The guardian node has returned to LASER_UP. However there are a number of SDF differences remaining. I have accepted them (screenshot attached). Set back to observing at 02:40 UTC. Just got kicked back to commissioning again. Same issue...
Trying again. Accepted SDF differences attached.
Got kicked out of observing again while I was out of the room. Setting back to observing. SDF differences attached.
Here I attached some plots regarding the event to compare to what happened last time.
This looks like it started with the spike in the lsrpwr_hd_pd channel. That is the measurement channel for the laser output power that is used to stabilize the laser.
There is then a corresponding correction to the PZT position, and a change in current to the laser associated with this move. After that the slower temperature change happens to bring the PZT voltage back to the middle of its range. This all happens in the first 1/3 of the plots shown here. By the middle of the plot, the laser is unlocked and trying to relock.
Firstly, I suspect that spike in laser power that triggered this may not be real. We should take a closer look at it, but it may be related to the other spikes and jumps you're seeing on the Y-arm laser.
Secondly I think we should revisit the intentions for this laser locking system. It is meant to keep the power of the laser relatively stable, not to kick us out of observation mode.