Alexa, Kiwamu, Lisa

Most of the day was lost in ALS land. We manage to start locking at 2am. Our success was pretty well correlated with Kiwamu changing the Y end VCO offset slider from -0.263 to -5.526 such as the X VCO goes away from the negative railing point when DIFF is locked. This was done because, even if the HEPI relief was on, we were seeing that at least some of the ALS lock losses were due to the X VCO railing (to be investigated).

After that, we worked on ASC during the CARM offset reduction. 

So far we have been using AS_B_45Q for DHARD until CARM offset = -12, then we were opening it because we suspected that this signal was flipping sign when reducing the CARM offset further. Tonight we indeed established that by measuring the response to ETMX steps by comparing CARM offset -8 and -13. At the same time we checked the AS_A_45Q response, which is still sensitive to DHARD but it does not change sign.
After measuring the relative gains, we transitioned from AS_B to AS_A at -13 CARM offset, and then we kept the loop closed while reducing the offset down to -16.

Some parameters:

 - AS_A input matrix elements are +2e-6 for both P and Y (ugf ~50mHz).

 - We also reduced the SRCL gain by a factor of 2 (from -30 to -15) at CARM offset -15, and that reduced the broad gain peaking we were seeing in the SRCL spectrum at 70 Hz (we didn't really make any measurement).

We are not updating the Guardian, as this needs further testing.

Data: Dec 3, 11.15 UTC locking start, lost lock at 11.56 UTC while transitioning to -16