This afternoon was devoted to the HWS-INJ activities.

As previously done for HWS-DET, we removed the HWS and installed the CCD camera in its place after grounding the EIB. This activity was performed after the Daily Meeting, between 13:30 and 15:00 UTC.

The HWS-INJ SLED beam was switched on and appeared to be well aligned on the CCD camera. Figure 1 shows the beam on the CCD with the ITF set in WI single bounce, the PR aligned, and the SLED voltage set to 2.3 V. Also the additional loop on MIR has been enganged by Manuel.

To make sure that the observed beam was indeed the HWS beam reflected back from the WI, we switched off the green beam and tilted the WI TM to check that the beam moved accordingly on the CCD camera, which was indeed the case.

After that, the SLED was switched off in order to replace the CCD camera with the HWS.

The HWS illumination is shown in Fig. 2, with the ITF set in WI single bounce, the PR aligned, and the SLED voltage set to 1.4 V.

15:04 UTC: HWS acquisition started

15:12 UTC: WI RH ON (wavefront 5)

The RH signature is visible at the edge of the HWS map (see Fig. 3), suggesting that the SLED beam is not well centered on the WI mirror.

16:54 UTC: WI RH OFF (wavefront 55),and the additional control loop was disengaged.

During the same acquisition, we switched on the WI CH to check its position on the HWS map.

17:50 UTC: WI CH ON (wavefront 80)

The CH-induced OPL corresponds to the blue area shown in Fig. 4.

19:31 UTC: WI CH OFF (wavefront 131)

As the last activity of the day, we performed a rough alignment of the CH with the RH. This will allow us to use the CH as a reference tomorrow, when we move the HWS beam using the steering mirrors on the EIB.

STEP 1: Movement of HM by 3 cm (15000 steps) backward in TX

STEP 2: Movement of HM by 2.1 cm (12000 steps) forward in TY

19:59 UTC: WI CH ON (wavefront 144)

We concluded the activity at 20.46 UTC.
Lorenzo will relock the long arms.
Tomorrow, we will start with another HWS acquisition to check the new CO2 actuator position.