Dan B, Terra H. Alexei C., Seb N, TVo
We attempted to try to characterize the SR3 RoC heater's modematching range by mode scanning the OMC. However, we had trouble getting the OMC alignment loops to close. Even though the alignment on the QPDs using OM1 and OM2 were relatively close to the loop offsets to start, the OMC SUS would rail and push the beam off of the QPDs. We've had this problem before but we couldn't figure out what the issue was this time around. Although we got flashes in the OMC, the misalignment was not good enough to get a proper measurement so we'll have to try again some other time.
FYI: For the upcoming vent, we've turned off the SR3 driver and left the IMC locked with 2.5 W input. Also, a lot of the digital cameras weren't loading for some reason, even after requesting a reboot.
It looks like the fast shutter closed at around 5:30 UTC last night, which would make it impossible to close OMC QPD or AS centering loops.
I agree, but there was still light on the QPDs even after the fast shutter said it was "closed". So that makes me think that it was still actually open. This seems very odd to me. Keita's alog here shows some step-by-step instructions on how to use the shutter but I still don't fully understand the logic.