Alexa, Keita, Evan, Kiwamu,
We noticed that the input pointing degraded by some anomalously large amount during some locking activity. This was quite noticable. For example, the PRX build-up at ASAIR_A_LF dropped roughly from 4000 to 3000 counts.
After some detective work, we found that the MC1 and MC3 suspensions moved by roughly 100 urad in pitch. It was the DOF_3 loop in IMCAS that was pushing these suspensions pretty hard. Eventually we found that this was due to the MC2 trans picomotors which had been moved supposedly by some IMC/ISS activity. Since this configuration seems to give a higher cavity power in IMC, we are leaving as it is and fix the IM4 and PR2 angles to compensate it. The attached is 4 hour trend of various IMC-related signals. It is obvious that as the picomotors moved the suspension were also moved, resulting in a different pointing at the IM4 trans QPD.