Follow on from alog 61944. TJ Shaffer, Camilla Compton.
Today we adjusted ITMY HWS pointing to remove the clipping by adjusting pico motors below and last steering mirror HWS M10. Final photos attached with and without plate. I have got a controls tmux session on zotws14 to run a ITMY 0.5W ring heater test 2am-5am.
| Picomotor - all started at position (0,0) | X (Yaw) | Y (Pitch) |
| #3 HWS Y Lower Periscope | 444 | 100 |
| #4 HWS Y Upper Periscope | 1632 | 4800 |
| #5 HWS Y M1 HAM4 | -2354 | -733 |
| #6 HWS Y M2 HAM4 | 1800 | 3967 |
ITMX HWS beam (photo) is not clear and must be clipped somewhere. We will revisit when we can move SR3 to quickly search for our HWS beam and/or use ALS to chekc for ALS beam near camera.
I went to look at the results of the RH test and noticed that the ring heaters never turned on (the EX test seemed to work though). I went to the CER and found the RH driver chassis off. Flipped those and and also flipped the TCSY HV on because I forgot if the RHs were HV or not (TCSX was already on). I started a RH test on ITMY at 9:03am (1330189405) at 1.5W and I'll leave it run for an hour.
Slight delay this morning with RH tests as I forgot to check on SR3, which was in SAFE. After doing it the correct optics aligned, I got an odd result. It looks like there is something that is streaked accross the image in the middle at a ~30deg angle from the horizontal. I have no idea what this is, but it might be worth checking the beam with the plate off again when we are in laser hazard and checking optics for a hair or something.
I ran the ring heater for ~1 hour at 2W using the RH filter Guardian. The first attachment is during heating, second is during cooldown.
While we were in hazard today I removed the Hartmann plate from the HWSY camera. You can see a faint vertical line at 0. It looks like a mismatch of intensities. See attached photo. This is a different rotation to the line TJ saw but maybe the script rotates the image when it gets recentered? See attache photo.
This isn't physically part of the beam as stayed still when the beam was when pico-ed. I tried the power cycling the camera (power supply on floor) and RCX Clink (by turning 'Corner Distribution box' OFF/ON) and rotating the plate holder and filter but the line didn’t change.
I will leave the plate off but we look into what could be causing this.
The vertical line at the center is caused by the CCD on the camera having two readouts. The left side and the right side of the CCD are read out and digitized on separate ADC units. This is normal for the CCD. The gain/bias of the two ADCs are not exactly matched and so yield very slightly different values for the same number of electrons.