At some point within the last year, both the X and Y-axis accelerometers (PEM-CS_ACC_LVEAFLOOR_HAM1_X and Y) were kocked off (pictured here) the small metal cube they were mounted to. I reattached them as of Nov 11, 2025. I believe the capacitor position sensor box was pushed back into the accelerometers which knocked them off. Image 3 shows where the CPS box is in relation to HAM1 (circled in red) and image 4 shows where it is in relation to the accelerometers.
Additionally, two other accelerometers have been remounted with epoxy in August: PEM-CS_ACC_BEAMTUBE_SRTUBE_X (remounted August 5, 2025) and PEM-CS_ACC_BEAMTUBE_YMAN_X (remounted August 12, 2025). Both had fallen off the beamtube and had been hanging in the air for an unknown amount of time until someone noticed.
The HAM 1 floor accelerometers appear to have been moved on or around April 18, 2025 during the HAM1 work during the break between O4c.1 and O4c.2. The coherence between the two signals dramatically changes character after that date. I attach some plots of the coherence between accelerometers the day after you repositioned them, as well as data from 0000-0100 UTC on a few example days. I'm not sure that it was moved exactly on April 18, but the coherence data begins to differ from the reference on that date.
