- IMC alignment and measurement of the new AA sensing matrix

- IMC longitudinal wp. The offset on the IMC PDH error signal appears to be quite large (-1.6 V, see attached plot). However, with this offset the IMC lock is very unstable, so we left the old one -0.07 V. To be understood why the scan gives such large offset (maybe on monday we will check the alignment in the EOM? on the IMC refl photodiode?)

- IMC Fmoderr. We made it with the automation and it was very close to the optimal wp

- IMC angular wp --> we found an issue on the NF V RF quadrant.  We did the usual scans of the galvo working points (scanning the offsets of the galvos) and look at the coupling between error signal and frequency noise (TF between perturb at 1111Hz and the Quadrant signal (the demodulated quadrature I). We observed a strange behaviour for te NF V (non linearity: changes slope around the 0). See plots 2 and 3 which compare current scan (30 Apr 13:17:02 UTC) with an old one (10 Apr 2026 10:03:10 UTC): the magnitude doesn't go to zero and the phase behaviour looks strange. We then went in the LL Atrium and unpowered and powered again the NF QPD electronic box and made another scan at utc2gps(2026,04,30,15,05,08) from -0.5 to 0.5 in 300s (plot 6 and 7), which was still bad. To be investigated next week.

- IMC OLTF we found 96 kHz UGF and 30 deg phase margin. We added 1 dB to get 107 kHz and 23 deg phase margin (plot 8)

In the meanwhile we prepared the Acl code ISYS_BPL for the bench pointing loop. We still have to plug the PZTs to the DAC (we need prior to find a solution to block the beam before the EOMs while testing the PZTs, since the risk would be to burn something)