Starting from the entry 56432, the goal of the shift was to continue the centering of the DET-HWS beam on the NI and to start the centering of the INJ-HWS beam on the WI.

We decided to do another movement in the vertical direction acting on the EDB_Har_M1 (figure 1).

To be sure that nothing moves during the measurement, as agreed with the commissioning coordinator, we decided a procedure to follow:

• Starting with locked arms;

• Misalign the arm that isn’t involved in the measurement and align the other one;

• Start HWS acquisition;

• RH switching on;

• Relocked the arms;

• When the transient will be finished, misalign again the arm that isn’t involved in the measurement and align the other one.

In this way not all HWS wavefronts are reliable because the ITF configuration changes during the measurement, however for the RH we aren’t interested in what happens in the first 1 hour of the transient but we are sure that the mirror doesn’t change position during the measurement.

So, at 08.40 UTC we started the DET-HWS acquisition, at 08.49 UTC NI RH was switched on @7.5 W and at 11.20 UTC it was switched off. Some signals, the last wavefront and the center coordinates behavior after about 1 hour are shown in figure 2, 3 and 4 respectively.

We are satisfied with this result. After that, we went on EDB and we replaced the DET-HWS with the CCD to better align the coming back beam moving the mirror before the sensor.

The two last missing checks are: switch the RH to take the center reference; switch on the CH to see if it is still aligned.

Using the same procedure mentioned above, we started the alignment of the INJ-HWS beam. The starting point is that of the entry 56333.

First, we moved EIB_Har_M0 (figure 5) in the vertical direction.

At 13.57 UTC we started the INJ-HWS acquisition, at 14.03 UTC WI RH was switched on @7.5 W. Some signals, the last wavefront and the center coordinates behavior after about 1 hour are shown in figures 6, 7 and 8 respectively.

We went on the EIB and I did another movement equal to the previous one and we better aligned the coming beam, as done on EDB. At this point we repeated the measurement. The results are shown in figures 9, 10 and 11.

The same two checks seen before for DET are missing. Furthermore, for the HWS-INJ, a re-centering of the beam on the sensor is needed, which will be relevant for the CHRoCC characterization and commissioning. 

Julia left the arms locked on the IR and I left the TCS powers in the following condition: