(Elenna C [in spirit], Ibrahim A, Corey G, Tony S, Jim W)

Summary:  H1 survived a magnitude 6.0 EQ in Alaska via new ASC High Gain button/state.  This preserved a 24+hr lock.  This probably saved us (at minimum 2.5hrs of downtime!):  (1) ~90 min for the earthquake seismic noise to die down & (2) for 1-2hrs of locking.  L1 went DOWN due to this EQ about 20min after we saw it rolling through LHO!

Had my first experience getting to ENGAGE the new RED "ASC Hi Gn" button (see Elenna's alog) for an earthquake!  This tool is still fairly new and "manual" (& cool!) for operators.  Main items for engaging at this point (for me, as a newbie) was waiting for SEI_ENV to go to EARTHQUAKE mode and also watched for any colors on the Picket Fence.  While we were dealing with this earthquake, Jim walked in to also observe and answer questions for us; Ibrahim also gave advice since he's engaged this EQ mode twice.  All the details for what happened are logged below.

How Everything Went "Down"!

2102 VerbalAlarm:  "EQ alert for M6.0 in Aleutians"  (it said "Incoming earthquake from Canada")

• 2111 Seismic:  EQ Mode Activated! (due to R-Wave arrival)
• 2112 Out of Observing & clicked Earthquake on Observatory Mode
• 2113 Hit the "ASC Hi Gn" (red) button (on this bright green pop-up terminal, I typed in "yes".....but had to open another one, because it only needs "y").  Within a minute or two, the script completed the transition to "ride" out the earthquake.
  • Also around this time, started seeing yellow on picket fences, followed by some oranges.  This EQ started to show up as a big spike on the earthquake band on the wall (see 1st attachment).
    • Also saw this EQ in secondary microseism.
  • 2114 ASC oscillations appear
  • 2116 ALL Picket Fences are yellow or orange!
  • 2117 Peakmon reaches max just a hair under 2500 nm/s on Peakmon
  • 2117, 2121:  EX saturations on VerbalAlarms
  • (2134 L1 goes DOWN due to EQ....2nd attachment for the earthquake when it took L1 down)
  • 2154 Seismic back to CALM
    • SEI_ENV took about a minute or so to make the transition to CALM (all guardian nodes on ISI_CONFIG eventually go green).  Once everything was GREEN....
    • On ISI_CONFIG, clicked the blue "ASC Low Noise" button & this pops up another bright green terminal, and I entered a "y" and this transitioned H1 back to NLN with our usual High Sensitivity.
  • 2157 H1 Back to OBSERVING!
  • (2254 L1 back to OBSERVING)