TITLE: 06/08 Eve Shift: 2300-0800 UTC (1600-0100 PST), all times posted in UTC
STATE of H1: Commissioning
INCOMING OPERATOR: OWL Shift Canceled.
SHIFT SUMMARY:
The Plan for tonight: Tony will power up on RF to avoid the difficulties we have with turning on a DARM offset. Stop at 10W, which is the smallest power at which we saw a pressure spike yesterday, and intentionally unlock (request down or flip sign on IMC servo). Check for a pressure spike. If there is no spike, repeat this until the end of Tony's shift when he will leave the IFO in DOWN. No owl operator. In the morning, @Keita Kawabe @Corey Gray and I will chat on zoom at 9 am, to discuss next steps, and what is needed for debugging the locking issues. @Jenne Driggers I think that today's locking situation is very similar to what you alogged on Wed, we were able to turn on the DARM offset once when I opened the SRC1 loops and aligned SRM by hand to reduce POP90.
What Actually happned:
Got stuck at locking DRMI for the entire night trying different alignments and troubleshooting tips.
I moved the BS and PRM around so much that I could no longer convince ISC_lock to go to AQUIRE_DRMI_1F any longer again.
So I went back to do an Initial Alignment. interestingly enough I ended up in the same spot as last time where I was stuck in AQUIRE_SRY, I touched up PRM by hand again as best I could while watching AS_AIR and ASC_AS_A_DC Sum again. once I got that as maxed As i could get it, I lowered the threshholds again.
H1:LSC-SRCL_TRIG_THRESH_ON from 0.006 -> 0.003
H1:LSC-SRCL_TRIG_THRESH_OFF and 0.004 -> 0.002
Allowed Initial_alignment to complete again.
And once ISC_LOCK got back to locking DRMI I was greeted with another instance of the beam splitter or PRM being off in YAW by a lot.
I then held ISC_LOCK in AQUIRE_DRMI_1F & set the slider values for PRM and BS to the value that they were at during the last lock with DRMI. This did not work either.
I tired this a few more times using different places along the locking process.
Rolling ALL sliders back to GPS Time 1401839323 (the IDLE time before the last time we had a locked DRMI.)
I was hesitant to revert ALL sliders back because I was under the impression that there was some significat work done on that particular alignment.
All sliders restored to GPS time: 1401762164 (Tail end of Initial alignment before a good lock)
The Alignment is off somewhere, And I'm not sure where.
I stayed a little late to try one more thing:
I restored back to a know good alignment, then ran another initial alignment on top of that! but I did't move SRM in the SRC ALIGN IFO stage. instead I just quit the Alignment.
This resulted in an alignment that got DRMI locked but SRM saturations were constant and I got stuck in DRMI_LOCKED_CHECK_ASC because the SRC channeles were not converging.
I tried this again and tripped the SRM SUS WatchDog. I have now taken ISC_LOCK to Down for the night.
LOG:
Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
---|---|---|---|---|---|---|
21:03 | SAF | HAZARD | LVEA | YES | LVEA is Laser HAZARD | 23:31 |
15:24 | isc | commissioners | cr | - | OFI pointing | 00:21 |
17:10 | SHG | terry.KarMeng | OpticsLab | YES | SHG green/ir laser work | 23:54 |
23:22 | PEM | Robert | LVEA input arm | YES | Taking temp View Port Covers *OFF* to look inside! | 01:22 |
01:36 | PEM | Robert | LVEA | YES | Putting Temproary ViewPorts on | 01:40 |