TITLE: 11/25 Eve Shift: 0030-0600 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY:

IFO is in NLN and OBSERVING as of 17:12 UTC 11/24 (~13 hr lock!)

Extremely quiet shift. Intentionally dropped out of OBSERVING twice:

1. To let Vicky tune SQZ while L1 was down. Sadly, this did not seem to improve range. We were COMISSIONING between 04:19 UTC and 04:31 UTC (12 mins)
2. To damp EY Mode 1. Vicky noticed DCPDs were growing and asked if Violins were high. Upon trending (screenshot), it seemed that EY Mode 1 had been increasing for the whole lock. I had to go to DAMP_VIOLINS_SIMPLE, which took us out of OBSERVING between 04:53 UTC and 05:12 UTC (19 mins). Applying the nominal gain of 0.1 did not work, so I played around with the gain, increasing it by a further 0.1 and decreasing by 0.05 both in the negative and positive. While there were some short term successes, overall my attempt did not help, with counts always seeming worse than with nominal guardian damping (which is 0 gain). Not wanting to spend too much time out of OBSERVING, I re-set the gain to 0 and gave guardian the reigns again. They're ever so slowly going down.
   1. My guess is that these violins are being rung up by the increasing secondary microseism, which started noticeably increasing around 8 hours ago. It is about to cross the 0.9 threshold line. The primary microseism is also elevated as of 13 hrs ago.
   2. EY Mode 15 is also elevated, but judging from the 1000(ish) hz lines on DARM and the value on the cts, it is by a negligible amount (still below 10E-17 ASD), so I did not attempt to damp this.
   3. For our recent locks, it seems as though the damping works up to 1-2 hrs into locking but then Mode 1 turns around and starts increasing in counts. I believe some more investigation into this is needed to perhaps find a better angle/gain to damp. (screenshot 2).

LOG:

None