[Takahashi, Aritomi, Yuhang]

Since BS suspension motion was too large and the pitch picomotor can move in only one direction, we opened BS chamber and checked suspension. Takahashi-san found that the magnet was touching the coil holder so he adjusted it.

Regarding the picomotor, the picomotor cannot move in one direction because the required force to move the picomotor in the direction was too large. To reduce the required power to move the picomotor, Takahashi-san put a spring (Fig. 1). Then the picomotor can be moved in both directions.

We aligned PR and BS to make the green beam at center of the GV between input/BS and the first target.

Before closing the chamber, we checked BS oplev transfer functions (Fig. 2,3) and response of each coil. The transfer function and coil response are fine.

Finally we closed the chamber and started the evacuation of BS chamber.