This afternoon we performed some measurements to verify the mismatch towards the arms. The last measurement done is reported in #63374.

First, we performed the free swinging method, giving a kick on the end mirrors (with the dampers opened). The GPS of the kick (we gave the kick simultaneously for the West and North arms) is 14:17:00 UTC.

However, when analysing the data we could not find reasonable values of mismatch. We need to verify if there is any problem with the Matlab code to debug, or there was something wrong with the measurements. In Fig. 1 we can see the time window of the free swinging mirrors. To be noted that the west arm starts swinging after roughly 15 seconds with respect to the North Arm. On Fig.2 we can see the surposed flashs of B7 and B8.

Then, we perform the measurements with the Green Scan. The GPS in this case 14:30:43 UTC (Fig 3). Figs 4 and 5 show the scans of the TEM 00 mode and TEM 02 mode respectively. In this case, for the north arm we found 3.3% and 1.4% for the west arm, as shown in Fig. 6.