The shift of yesterday afternoon was dedicated to the DET-HWS beam centering. Starting from the situation of July 4th (entry 56345 and figure 1), we knew that we should do a movement of the beam mostly in the horizontal direction.

At 14.16 UTC we closed the NI CH to cool down the CP and to take another reference. Then, the DET-HWS acquisition was started and after 5 minutes the CH @ 384 mW was opened, but we saw a strange behavior in the wavefront, even when the CH curvature was at the steady state (figure 2).

We decided to do a little movement in the horizontal direction acting on the EDB_Har_M1 (figure 3), in the meanwhile we switched off all the NI actuators. We switched on again the CH and we started a new HWS acquisition. The situation of the wavefronts hasn't changed (see figure 4). Probably, there were too transients ongoing at the same time.

At this point, we decided to switch on the NI RH in order to verify that the movement had not worsened the alignment, instead of improving it. We confirmed we did the right movement, see figure 5.

Center RHs coordinates:

July 1st: Y=(-2.5+-0.3) mm and X=(26.5+-0.5) mm

July 11th: Y=(-27.6+-0.5) mm and X=(5.8+-1.4) mm

Performing another HWS acquisition, we switched on the CH @ 392 mW to verify if the CH was visible. Something appears in the wavefronts, but not yet clearly enough.

At 21.03 we switched off all the NI actuators and the NI RH in order to have the CP cold today morning.

We performed a similar movement in the same direction of the previous one that we will verify.