Went to EY. The power coming out of the fiber was 174 uW.

Originally the Prometheus red crystal temperature was 42.36 degree C. We ended up lowering it down to 31.39 degree C to get a beat note.

The green power dropped by about 20% judging from the QPD sums (e.g. QPDB sum used to be 7500, now it is 6000) and H2:ALS-Y_REFL_B_PWR_INMON (uset to be 12700 unlocked, now it's more like 10200). I changed the offset in REFL_B_PWR accordingly. This means that the old 8000 counts is now 6400 counts.

The waveplate for the fiber output was adjusted to maximize the beat note, which was about -39dbm. Turned on the servo, adjusted the temperature knob several times to relieve the slow temperature servo, and it worked OK.

We measured the OLTF of the PLL even though there's no reason it should change. The UGF was about 23 kHz.

See Jax's entry about the green power going to the chamber and the actual data of the PLL OLTF.

Now the arm locks.