[Ono, Komori, Yamamoto, Ushiba, Fujimoto]

We tried implementing the feedforward technique to reduce the MICH control noise in the current DARM sensitivity.

In this feedforward, the MICH out was sent to the ITMX actuator through the appropriate filter.
This filter should be (TF from MICH out to DARM)/(TF of the ITMX actuator), and it was ~0.022.

We implemented the feedforward filter and tuned its gain monitoring the DARM sensitivity.
As a result, the sensitivity was improved by a factor of 2-3 at 50-80 Hz (red line: w/ feedforward, green line: w/o feedforward).
The obtained data was saved in /users/Commissioning/data/DARM/2023/0216/MICHFF_DARM.xml.
For the further reduction in broad frequency range, we need to investigate the transfer function from MICH out to DARM under the feedforward firstly.