We entered the DET lab at approximately 8.00 UTC. For the duration of the activity, Nicola set the DET lab HVAC system to high-speed mode.
We first unplugged the power supply and all the cables of the link located behind the HWS. We then removed the HWS camera and installed the CCD camera in its place, restoring all the required connections (see Fig. 1).
Afterwards, we went to the Detection Electronic Equipment Room and physically switched on:
-
the HWS-DET power supply
-
the DET SLED power supply
We then attempted to connect to the CCD camera. The camera initially had to be reinitialised, after which the connection was successfully established. We set the SLED-DET voltage to 1.0 V and started to observe a signal on the camera.
Once Nicola confirmed that the required interferometer configuration had been established, the conditions were as follows:
-
suspended DET bench correctly positioned, thanks to Nicola and Romain;
-
SR, BS and NI aligned
-
WI, WE and NE misaligned
We increased the SLED-DET voltage to 1.2 V and observed the beam clearly on the CCD camera. When the DET flip mirror was closed, the beam disappeared from the camera, as expected (see Fig. 2).
The DET SLED beam appeared to reach the NI mirror correctly and return to the sensing camera without any significant clipping.
The following actions still need to be performed:
-
reinstall the DET HWS camera in place of the CCD camera
- perform the same type of check on the INJ HWS/SLED system
We left the DET SLED turned on at 1.2 V and the CCD camera ON.
