(Alexa, Sheila, Evan)
As we were trying to lock ALS DIFF, we noticed that both the COMM and DIFF beatnote were too weak. We trended these values and found that the beatnote first disappeared when the PSL went down and then again at around 9am PST. I then tried locking the IR to the x-arm and found that I had to move PR3 by 4 urad in pitch to lock. The input wfs then moved IM4 and PR2 to increase the buildup. We suspect things got moved around again with the work and trips on HAM2, HAM3. We didn't spend too much time investigating the exact cause, and we did not want to go through the entire alignment to lock DRMI and check the POP18 counts since we want to focus on DIFF right now. Hopefully we didn't introduce a new clipping in the PR2 baffle by the amount we moved.
| OLD | NEW | |
| PR3 (P, Y) | (-246, 88) | (-242,88) |
| IM4 (P, Y) | (11414.2, -5002.3) | (14326.4, -5102.9) |
| PR2 (P, Y) | (1035.2, 2981.28) | (1006.9, 2973.95) |
IMPORTANT: I have not saved these new alignment values, so if the guardians get realigned they will restore the old alignment values.
Also, the beam in the AS AIR camera looks too far to the right.
I moved PR3 back to the old values, whic today gave us a better COMM beatnote.