cheryl.vorvick@LIGO.ORG - posted 00:25, Thursday 14 December 2017 (39753)
IO work 13 Dec 2017
- PSL beam aligned to the MC1 and MC2 irises
- IMC flashed, good 0-0 modes
- 0-0 modes were used to align MC2 Trans
- this means that we have a known good IMC alignment that centers the beam on MC2 Trans
- strong 0-0 modes flashed in each MC2 Trans QPD quadrant at around 700 (raw signal)
- variations in the height of the flashes in all quadrants was 20-30 counts, which is around 5%
- beam from the PSL was monitored, and checked on MC1 iris more than once today, and it appears that later in the day something happened, because my last check of the beam showed that it was off in yaw
- IM3 required a pitch adjustment, and this was accomplished without removing the baffle, because the locking collar on the pitch adjustment screw wasn't tight
- tightening the collar required removing the IM3 SiC baffle
- the Viton remained stuck to the SiC when the baffle was removed, which made reinstalling the baffle easier, however
- the weight of the SiC baffle further adjusted the IM3 pitch, so there is a pitch slider actuation
- the locking collar could be put on the back side of the adjustment screw, which would potentially make pitch adjustable without removing the SiC baffle
- each time it's required that we remove and handle a SiC baffle the risk of having one shatter increases
- IM4 is in the same situation as IM3, the pitch adjustment screw and collar are not currently adjustable with the SiC baffle installed on the IM4 cage
- the flashing beam from the IMC is aligned to the PRM Trans and PR2 irises