Noticed that the calibration for ASC-AS_C_NSUM was off by a factor of 2 indicating twice as much power as was actually there. Reduced the calibration factor by 2. The input to the NSUM block is calibrated in mW dedected by the QPD. The transmission of OM1 is 720ppm (E1100056). So, the calibration factor in W at the AS port is 1/1000*1/72e-6 = 1.39.

Added calibration factors to ASC-OMC_A_NSUM and ASC-OMC_B_NSUM. The splitter towards the ASC-OMC QPDs samples around 1.25% (E1000457). It then gets split equally between QPDs A and B. The input to the NSUM block is calibrated in mW dedected by the QPD. So the calibration factor in W at the AS portis 1/1000*2/0.0125 = 0.16.

Also changed the front-end model to use averaging rather than a straight sum for, i.e., ASC-OMC_NSUM = 1/2*(ASC-OMC_A_NSUM+ASC-OMC_B_NSUM). Same for ASC-OMC_RIN.