Some misbalancing of the MAR actuation on PR has been noticed.

By looking at the data this occurred during the measurement performed on vertical DoF of PR F0, which triggered to move the payload with respect to the F7 in vertical of around -700 um to a bistable position of the anti-springs (see fig.1: Sc_PR_F7_LVDT_V).

This eventually caused a loss in the accuracy of the PRty alignment loop, see fig.2 in which a stretch of data have been taken in LN3 before the misbalancing (blue) and after (red).

By looking at the TF between MAR Zcorr and TYcorr we measured the needed coefficient to adjust the actuation balancing (fig.3). This adjustment has been done this morning. Once we will have a PR cavity locked we will check the outcome of the action.