Terry McRae, Sheila

This afternoon Terry and I started to prepare for measuring the mode matching of the squeezer to the OMC. 

• We changed the crystal temperature as we scanned the OPO to find a co-resonance where there is much less nonlinear gain, so that we can generate a stable seed beam for alignment and mode matching.  With the OPO locked we see co-resoance for a temperature setting of 43.4C.  For nonlinear gain the co-resonance temperature in air is 33.47 C
• We injected this into HAM5 and saw some light on AS B.  With the fast shutter open (see 41409) we were able to manually move OM1+OM2 to center the beam on the AS WFS, which also put beams onto the OMC QPDs. 
• To engage the AS centering loops, we had to change the sign of all the gains.  This doesn't make sense, and it looks like there are lots of things that don't make sense in the SDF files for the OMs.  
• We need to set dark offsets on the OMC QPDs, this might have been part of the problem with using OMC alignment loops that our mode matching crew have experienced.