Although the morning MC tuning looked stable, Koji pointed out that the MC_REFL_OFFSET was changed from its nominal value.
The offset was reset and this caused drift in the MC_TRANS_SUM.
To fix this:
- disabled the WFS servo
- aligned MC using MC1 and MC3
- centered beam on the MC_REFL
- reset WFS offsets
- locked MC
MC looks happy now.
ALS is in a very different state from a couple of days ago when we could successfully lock the arms and scan.
The green alignment to the arms had drifted.
PSL green alignment on the PSL table was off. The PSL green was not even on the steering mirror. Did anyone work around the PSL table in the last couple of days?
After aligning and finding the beat note, I found the ALS servo very noisy. The error signal had 10 times more rms noise than what was achieved earlier this week and there were some new 60Hz peaks as well.
Overall, we could not do any PRMI+ALS arms today