betsy.weaver@LIGO.ORG - posted 11:20, Wednesday 10 June 2015 - last comment - 16:10, Wednesday 10 June 2015(19049)
ESD/charge measurements have ~commenced - status report on IFO
We attempted to set up the IFO for some end station ESD measurements around 10am. During some of the switch settings, the IFO lost lock. Relocking is ongoing with help from commiss. A suite of ESD/charge measurements have become increasingly more important, hence time has been allotted today.
I was asked by Keita to update the ETMX actuator calibration path for their charge measurement in full lock. I updated the foton filter of CAL-CS and a few settings associated with the simulated ETMX actuators in CAL-CS. The SDF is updated accordingly. We are now temporarily using the simulated ETMX in CAL-CS by switching the output matrix as of around 2015-06-10 19:00 UTC. We did not touch the ETMY actuator path at all.
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The changes I made are:
With Keita's guidance, we calibrated the TR QPDs to the ETM OPLEVs to get a calibration constant which will be needed to interpret the charge data being taken. We found the calibration by driving at the L2 stage at 6Hz and watching the QPDs and OPLEVs. Note, the Y-arm QPD TR B was not as well centered as the X-arm TR A and B and X-arm TR A.
Here are the calibration numbers:
Keita has completed the ESD/RH charge measurements for ETMx and ETMy, however he is still chewing on the numbers. He expects to post something later today.