Yesterday, around 14h22 utc, we have introduced two new channels : DET_B1s_DC and DET_B1_DC.

These are calibrated versions of SDB2_B1p_DC and SDB2_B1_DC (in the last case, the calibration factor between SDB2_B1_DC and DET_B1_DC is currently equal to 1).

The calibration factor of DET_B1s_DC accounts for the expected optical transmission of the optics between the OMC and the B1s_PD1 photodiode. However, as shown on the attached figure, the reconstructed powers on DET_B1s_DC and DET_B1p_DC are quite mismatched (B1s seems to be overestimated with respect to B1p, or B1p is underestimated...). This is very likely explained by the multiple uncertainties on these calibrations (uncertainties on the photodiodes calibration, and uncertainties on the optical transmissions which can depend on the exact polarization content of the beam).