jenne.driggers@LIGO.ORG - posted 18:32, Wednesday 24 January 2018 - last comment - 20:14, Wednesday 24 January 2018(40263)
Clicked the big earthquake button
I'm not sure what "very large" means for earthquakes when it comes to something that seems borderline-ish, but it seems like this 6.4 in Kamchatka might qualify, so I clicked the very big Very Large Earthquake button. It was after the S-waves had arrived, but about 400 sec before the R-waves were expected.
The IMC unlocked, and ITMY's ISI tripped, although I'm not sure if that was before or after the transition was complete. I leave it to Team Seismic to investigate further if they feel so inclined.
It occurs to me that perhaps we need a "go back to regular" button, somewhere near the large earthquake button. Maybe this will be less relevant when we have operators who already know what to do, sitting in the chair. But, for now we'll leave it this way overnight since the EQ is still ringing down.
I've been planning on a wax on / wax off script to do this, but haven't done it yet because I wanted to be clever about it. I can put a dumb version on the ISI config screen tomorrow, but for now, going to the SEI tab on sitemap, opening the Transition_all_SEI (or something like that) and pushing the button to re-isolate all the chambers, and moving SEI_CONF back to WINDY will probably be close enough. This will miss some sensor gains, but they probably don't matter all that much. HAM6 and ETMY will probably trip because they are locked & their hepi iso gains are forced to zero on the secret slider. You could take both of those chambers OFFLINE after pushing the other buttons, or just let them trip.
Also, looking at the wall blrms, I don't think the transition was needed for this eq, just going to SC_OFF or LARGE_EQ for SEI_CONF would have been safe. It would be helpful to know what seismon predicted for the surface velocities.