Calibration factor: The calibration was done by sending 4Hz with 5urad expected motion (driving magnitude is shown in elog2216). (I didn't consider yet the transfer function of pitch/yaw. Since 4Hz is not far from resonance frequency, the pendulum effect is temporary neglected.) Beside, looking at the noise spectrums, at 4HZ, there is not the effect of AA loop. Then I check the peak value at 4Hz. After subtracting the offset (value at 4Hz without excitation), the value is divided by 5urad. Then I get calibration factor. I use it to calibrate the spectrum measured from wavefront sensor.

The measurement result is shown in the attached figure. (REF0,1,2,3: AA loop on. REF4,5,6,7: electronic noise. Others: AA loop off. )

1. From this measurement, End mirror is moving less than Input mirror.

2. The RMS motions of Input mirror reach about 7urad for both pitch/yaw.

3. The RMS motions of End mirror reach about 2urad for both pitch/yaw.

4. The spectrum is well above the sensor noise.

5. The control bandwidth situation could also be seen from this measurement. The control in yaw direction has larger bandwidth and reach about several Hertz. The control in pitch direction has smaller bandwidth, but also reach about 1Hz.

6. It seems that the coupling from pitch to yaw is not small. The peaks in pitch (around 8-9Hz) is visible also in yaw.