Long Maintenance/Preventative-Maintenance Day Today
Once Jason & RyanS finished their PSL work on the floor (and some observing of the IMC for glitches in the Control Room), went for locking at about 515pm PST---with an INITIAL ALIGNMENT which completed with no major hitches. For locking, we continue to get Locklosses before/at LOCKING ARMS GREEN (so held at READY for a bit....but we had to wait a few minutes for the IMC to lock). Once we got past this, went for our first lock of the night.
[µseism is still very high, but winds dropped from 30mph down to 10mph]
Lock #1: LOCKLOSS for H1 at TRANSITION FROM ETMX[557] (which is noteworthy because Elenna was wanting to see if the lowered T-Ramp (alog81224) at LOWNOISE ESD ETMX [558] and we didn't get to see this. Vicky looked at this lockloss and sadly this LOCKLOSS was one of our infamous PSL/IMC Glitches.
Lock #2: After the lockloss above, DRMI looked pretty bad, so I took it to PRMI (but it also needed CHECK MICH FRINGES). After that, H1 went all the way to NLN automatically. The Violins were high (~500Hz peak was at around 1e-15), so we had to stay at OMC WHITENING for 20min before going to NLN. Then there were a list of SDFs which were all ACCEPTED (see below and attached). H1 to OBSERVING at 0340utc with a range hovering just under 160Mpc.
Maintenance Day Notes:
- No Sweep of LVEA was made---so this should be done at next opportunity
- Cable left plugged in from Monday (see alog 81194)---(probably would have been caught if Sweep was done)
- Wifi turned off for LVEA & MY a few minutes after going to OBSERVING.
SDF Diffs That Were ACCEPTED: (see attached)
- SUS: ETMy, ETMx, & ITMx all had a T-Ramp reduced from 10.0 to 2.0 seconds (alog 81224)
- PSL FSS: Common Gain increased from 13 to 15. Fast Gain increased from 5 to 6.
- PSL PMC: PWR_HPL_DC_GAIN increased from 0.0160515000 to 0.0477320000
Lockloss at 0442utc after about 1hr of Observing.
BUT---Vicky was saying this was a "normal" (i.e. not PSL/IMC glitch lockloss).
Lockloss #1 @ 1415499897 - likely PSL/IMC.
Standard PSL trends show FSS glitch, IMC, and IFO lockloss all at the same time (< 16kHz). Trends including SQZ not illuminating; see SQZ FSS glitch same time as PSL glitch (same time as lockloss), but not more info.
Lockloss #2 @ 1415508172 - NOT PSL/IMC! Looks like a "standard" (?) lockloss.
Standard PSL trends show that IFO and AS port see the lockloss ~200ms before the IMC loses lock. This was the typical lockloss before IMC/PSL issues. SQZ trends are normal; SQZ TTFSS and signals lose it when PSL FSS loses lock (again, ~200ms after arms see the lockloss), as expected.
