We aimed to do A2L steps over the weekend, 15 minutes/step 76630, 76683, but as Elenna points out with the camera servos running the beam spot stayed static on the mirror while the mirror actuation point changed.
Looking at data from A2L tuning in April 2023 68384 attached plot, A2L steps are ~0.4 for a change of around 2 in the camera offset (TRAMP 120s). We'll keep around the steps same as the weekend: +/- 1.0 per 15 minutes to up to +/-2.0 in the H1:ASC-CAM_{PIT,YAW}{1,2,3}_OFFSET channels during observing with nominal TRAMPs extended from 10s to 120s. These offsets are already unmonitered in sdf as reset each lock, I unmonitered the TRAMPs.
These offfsets vary up to 3 counts lock to lock, see attached plot. Set based on ADS converging.
Script saved in /ligo/gitcommon/labutils/beam_spot_raster/camera_servo_offset_stepper.py Scheduled to run if we're in NLN via tmux session on cdsws26 at:
- 6pm - 10pm on CAM1 (BS => CAM1 => PRM)
- 10pm to 2am on CAM2 (ETMX => CAM2 => ITMX, ETMX)
- 2am to 6am on CAM3 (ETMY => CAM3 => ITMY, ETMY)
Tony will be here during the first set so can cancel the others if there is any issues.
Jennie, Camilla
I looked at the CAM3 test from 08:58:40 UTC to 12:46:33 UTC and can see that a high offset (ASC-CAM_{PIT3, YAW3}_OFFSET) in both pitch and yaw corresponds to high power build-ups in the PRC and arms. Yaw seems to have more of an effect than pitch. The range dips when the offset is away from its nominal state. See first image. The offsets don't seem to have much effect on KAPPA C.
During the CAM2 test the IFO unlocked and so only the P2L steps seem to have run, its hard to see a trend in the build-ups for this as the IFO was still thermalising - maybe this hsould be run again. See second image.
For the CAM1 test the yaw steps were interrupted by lockloss so we will have to redo these.
The pitch steps for CAM 1 show optimum build-ups/power recycling at Pitch offset = -231.6 counts and worst at -229.6 counts. The range is worst when the build-ups are best and vice versa.
I am not sure why lower circulating power makes the range drop for all these measurements.
