[Jenne, Jennie, Keita, Jim, Sheila, Betsy]
Sum up: We're aligned pretty similarly to a reference time of [ 14 March 2026 02:20:00 UTC ], which is an "IR Found" time in between DRMI locks. We're back in the same place on IM4 Trans QPD as well as both forward-going POP QPDs. We have some mediocre PRX flashes. We are back (in the REFL path) on the same 3 of 4 PDs that we were before re-venting, so we should be in a good place for the team to work on REFL path things tomorrow.
Some details:
- Ref time for all optics *except* PRM is [ 14 March 2026 02:20:00 UTC ]. For PRM I take 20 mins earlier, at [ 14 March 2026 02:00:00 UTC ], when DRMI was locked.
- This ref time is when IR was found in the arms during main locking sequence, in between 2 DRMI locks, so the alignment should be overall pretty good.
- First I put all the optics [IMC, IMs, PRs, ITMX] back to their top mass osems (after figuring out that the DAC Kill was killed, alog 89676).
- Jim isolated HAM2's ISI. Jim had to unlock HAM3 HEPI to get HAM3 ISI isolated.
- I touched up optics to top mass osems again.
- Once JAC was locked, I got IMC locked. After the IMC ASC converged, I moved MC1 so that it was back to its OSEM place, which moved MC3 farther from its reference osem place. So, modulo HAM2 ISI slight change, the IMC is back to where it was I think.
- I then adjusted IM3 to get back to the reference time's place on IM4 trans QPD.
- I then adjusted IM4 to get back to the reference time's place on the two POP QPDs (they both were happy at the same time).
- This already gave pretty okay PRX flashes.
- I moved SR2 to get centered on AS_C. However, I hadn't checked the BS or SR3.
- I tried improving the PRX flashes a little with PRM, but wasn't making tons of progress. May need a bit of touching IM4 / PR2 in addition to PRM?
- We're seeing DC light on ASC_REFL_B, as well as both LSC_REFLs (although less on LSC REFL B than LSC REFL A). I have not checked or touched the RMs.
- Being on the same 3 PDs that we were while under vacuum gives us confidence that we're in a good place at least for fixing up the REFL path.
- The Saturday team may try locking PRX, or may defer to Monday. Either way, fixing up the POP path will probably happen after the REFL path.
The 4 attachments have vaguely descriptive names. The one from March 14th is my reference time, and then probably the other one that is useful to look at is the End of Day where I left things. I'm not sure I was seeing PRX flashes at the very very end of the day, so PRM might need some adjustment in the morning. The other two attachments are showing where the suspensions were before I started, as well as showing that I first got back to the reference time osem positions.
