To understand the noise contribution from PR/BS to the AA signal, we did several measurements and calculations. They are reported in elog2266 and elog2270. However, the sum of contribution was not done in the way of quadrature sum. So the results shown in elog2266 and elog2270 are not correct. Besides, elog 2270 used TFs which were measured without excitation. This should be replaced with TFs which are measured with excitation. This is due to that excitation can make the measurement of TF have more coherence. So we follow the same way of calculation with elog2270, except for the TFs and the noise sum method.

The measurement of TFs was done by exciting PR pitch, PR yaw, BS pitch, and BS yaw one by one. We call the measured TF with the style of TF_PRP_IP, which stands for the transfer function from PR pitch to INPUT pitch.

The quadrature sum of noise projection to INPUT pitch follows the equation:  IP = PRP*TF_PRP_IP + PRY*TF_PRY_IP +BSP*TF_BSP_IP +BSY*TF_BSY_IP. Here mirrors angular motion use name-style PRP to stand for PR pitch motion.

The results of noise projection and measurement is attached. Note that the data of PR/BS oplev signals and AA signals are directly from DGS. So the value itself doesn't correspond to a meaningful unit.

From this result, PR and BS angular motion are not the limiting noise of AA signals, except for INPUT pitch.