Abstract:
I calibrated CARM offsets at output bias of SUMMING node CMS (K1:ALS-SUM_OFS_SLOWOUT_CALI_OFFSET).
I also calibrated DARM offsets at output bias of PDH X/Y CMS (K1:ALS-{X,Y}_PDH_OFS_SLOWOUT_CALI_OFFSET).
According with the measured results, I modified FIND_IR_RESONANCE state in LSC_LOCK guardian.

Detail:
I scaned SUMMING node, PDHX, and PDHY CMS for calibrating CARM and DARM offsets with the condition of both ALS CARM and DARM were locked.
The reference of the measurement is FSR of Y arm, which is about 49.965 kHz.

Figure 1 to 6 show the time series data of Y arm transmission and output bias of the CMSs.
I measured the offset values for changing frequency by 1 FSR when offsets increased and decreased, and averaged them.
From these data and FSR, we can obtain the following calibration factors.

According with the results, I modified FIND_IR_RESONANCE state in LSC_LOCK guardian.