We ran charge measurements this morning and afternoon for both ETM's. We see no unexpected changes in the ETM charge trends, so we don't believe that any charge was accumulated from the 8.2 magnitude earthquake on Saturday (August 18, 00:19 UTC).
In addition to the quadrant-by-quadrant measurements, I've been running some additional pitch-and-yaw four parameter measurements on ETMX, as described in alog-42572.
I've still got sign and order-of-magnitude problems, but here are the trends over the last 4 weeks.
Alpha and gamma are roughly consistent over time, which makes sense as they are associated with the usual actuation strength. beta-beta2 and Veff are trending away from zero consistent with space-charge polarisation. The latest beta+beta2 measurement is strange, but maybe more data is required to interpret this.
I've removed the yaw results for beta+beta2 (bias), and the pitch for beta+beta2(signal) due to poor coherence between the oplev and the drive.
The only comparable measurement I can take on ETMY is beta+beta2 (bias) which does not require a signal pitch/yaw/longitudinal drive (impossible with a broken quadrant). ETMY's beta+beta2 (bias) is comparable to ETMX in pitch (4.5e-9 N/V), but an order of magnitude higher in yaw (3.1e-8 N/V), consistent with the higher response shown in the last plot of alog-43430.
