Reports until 16:50, Thursday 29 November 2018
H1 ISC
jenne.driggers@LIGO.ORG - posted 16:50, Thursday 29 November 2018 (45584)
New alignment post-vent

We've walked the SOFT offsets, as well as PRM and SRM pointing to get ourselves back to a PRG of ~48 (we were closer to ~39 the last few days since the vent).  It's not totally clear why the QPD setpoints needed to be made different, but we haven't checked how different (if at all) our input pointing is.

Hang reset the green initial alignment setpoints, and we set the IR trans QPD offsets, and the POP_A QPD offset, and now have the full ASC locked at this alignment.  Hang also rephased the AS72 while we were locked with this new alignment before we closed the loops.

We're not at the 0,0 point of AS_C right now (I've put an offset in that QPD as well), but we actually should move SR2 and SRM such that we're back to centered on AS_C so that we're going through the OFI nicely.

While sitting at 2W full lock for several tens of minutes, the 3.4Hz instability that comes from PRC2 Pit started to ring up.  For right now, we've engaged the lowpass that has the notch for this mode in it (it's an ELP6 that has a notch at 3.4Hz in PRC2_P) and that fixed things, but we'll likely want to remove this lowpass for the power-up.  Probably this isn't usually a problem for us since we don't spend large amounts of time here, and just get to LOWNOISE_ASC where that lowpass/notch is engaged in the guardian.