I set up a magnetometer by the high voltage input of the OMC piezo controller as another “shot in the dark” investigation of potential sources of blip glitches. I previously set up a magnetometer by the HV inputs to the ETMY ESD. I have been focusing on HV, because of the correlation between a class of blip glitches and low-humidity that Paul, Jordan and I found (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=28534). 

In related news, John W. and Bubba have started commissioning humidifiers. I suggest that we humidify VEAs/LVEA, electronics bays and MSR when the relative humidity drops below 7% inside of the buildings. Based on the high correlation between low inside humidity and low outside temperature last year (heating dries), an alternative that would give nearly the same threshold would be to start humidifying when the maximum outside temperature is going to be below freezing for more than one day in a row.

Channels

ETMY ESD HV: H1:PEM-EY_ADC_0_08,12,13_OUT_DQ

OMC piezo HV:  H1:PEM-CS_ADC_4_28_2K_OUT_DQ

Robert