J. Kissel

Your weekly charge measurement update from H1: ETMX and ETMY ESD systems are showing little-to-no effective bias voltage from accumulated charge. 

Recall we're flipping the bias voltage whenever the given test mass is not in use (i.e. ETMY flipped when DOWN [since 2016 Nov 28, see LHO aLOG 31929], and ETMX flipped when in nominal low noise [since 2016 Nov 03, see LHO aLOG 31172]). Since the regular flipping began, and our duty cycle has been consistently around 50%, we're keeping all quadrants below +/-10 [V] effective bias voltage, which is a small fraction of the requested bias voltage (~400 [V]), which means the actuation strength is changing at the sub-percent level, and is consistent with the uncertainty of the measurement.

We should confirm this by comparing against longitudinal actuation strength, a. la. LHO aLOG 24241.