J. Warner, K. Venkateswara
The LLO sensor correction was implemented at the rest of the test mass chambers, after installing it yesterday at ETMX. Plots are attached.
There is a significant difference in performance between chambers despite the CPS sensors showing about the same level of subtraction (~10). ETMY_Y shows only a factor of 2 improvement at 0.43 Hz, while ITMX shows the full factor of 10 improvement. We are not sure why this is the case yet, but we'll look linto the isolation loops tomorrow.
S. Dwyer, K. Venkateswara
Sheila helped me align ITMX. We then looked at the OPLEV to see if the sensor correction had improved the Pitch and Yaw of the optics. Once again, as we saw in 15498, the Pitch and Yaw remain unchanged, as they are dominated by Ry and Rz respectively as seen by the coherence. This will likely affect the cavity control as well, unless the WFS are on which we will try tomorrow.
Rz could be improved if we could reproduce Arnaud's results. Ry improvement will be harder.