After a back to back set of earthquakes and an initial alignment.
H1 has made it back to NOMINAL_LOW_NOISE @ 02:58UTC.
There were SDF Diffs I had to accept to get into Observing @03:01 UTC.
SUS-FC2_M1_OPTICALALIGN_P_OFFSET
SUS-FC2_M1_OPTICALALIGN_Y_OFFSET
Tagging SUS team to documen tthe SDF Diffs.
Tagging ISC and SQZ teams:
(1) Why are the FC2 alignment offsets monitored by the SDF system?
(2) Why would we have expected a change in the FC2 alignment? Is this concurrent and/or a result of other commissioning / optimizing?
1) FC2 alignment offsets in principle don't have to be monitored by the SDF system anymore, since we have commissioned ASC. While commissioning the squeezer, at some point it was helpful to do it this way before we set up ASC, but I don't think it makes a big difference now that filter cavity ASC is running. Sheila has already un-monitored several other alignment offsets in ZMs recently, so it should be fine to do that here as well.
2) FC2 alignment changed to help the filter cavity lock on a TEM00 mode after the string of earthquakes on Friday. There was significant pitch misalignment, so Naoki manually helped the FC green lock catch by aligning the FC2 (mostly pitch) slider. If FC does not catch green lock (similar to if ALS does not catch green lock due to misalignment) the system won't be able to go to FDS. So in this case, it can be nice to help it a bit by bumping FC2 P/Y sliders to get the green spot locking on FC green transmission camera (nuc33, bottom left).