We had an earthquake at about 3UTC. We changed the ISI configuration to LARGE_EQ, and brought it back to windy at about 5 UTC.
We have been sitting here with the green arms locked waiting for things to settle down more. The strange thing is that the X arm is moving 5 times more at the EQ frequencies than the Y arm is (see attached screenshot, the yellow and brown traces are both calibrated into um and shown on the same scale). I don't see anything different with the seismic configurations of the two arms.
This is probably due to the suspected rubbing on ETMX. First attached plot is 600 seconds of data from the around the time period in Sheila's plot. The top subplot is a reconstruction of the x and y arms using the E/ITM ISI cps (i.e. xarm = (exst2cps+exst1cps)-(ixst2cps+ixst1cps) ) and the ETMX st2 rx/ry loops gains*1e4 (so you can see the loops were 0 gain at this time). The bottom subplot shows the ALS REFL CTRL outputs, which to my eyes compare pretty well to the CPS reconstructions.
This morning I found the ST2 RX/RY loops turned off, there must have been a trip or something after I left yesterday? These had to be turned on by hand before, which is probably why they weren't on, but this morning I copied filters around and made the changes to guardian so the loops will turn on automatically now.
Second plot shows the same cps arm reconstruction from this morning after I turned the loops back on. Top subplot shows that the xarm motion is now similar to the yarm motion. The bottom subplot compares the xarm cps reconstructions with the ex st2 rx/ry loops on and off.
