Commissioning team

This morning we removed the half waveplates from the Y-arm green path that were installed on July 19. These were installed in an attempt to remove ALS COMM glitches (alog-42978), but they did not fix that problem. There was one waveplate on ISCT1, and one on the ALS table, between the periscope and the polarising beam splitter that combines the ALS and HWS paths.

We removed the waveplates because we thought that there was additional noise on the Y-arm WFSs after their installation but this turned out to also be unrelated.