The attached figure shows the corner of the PSL table (Especially Y side, The original file is in JGW-T1808565-v7).
Actually, alignment work itself is easy, but ALS optics are dense, so please be careful to do not interfere with other stuffs while working.
1. The value of fiber output should be 0.8 or more.
If not, adjust the PZT mirror just before the fiber (the blue circle in the figure) while monitoring the “K1:ALS-Y_ARM_INPUT_OUTPUT” to maximize the fiber trans beam.
2. After that, check the fringe value of the FIB cancellation interferometer by “ALS-Y_FIB_SERVO_IN1_DQ” .
Its should be over than -1000~1000 (like 13349).
If smaller than that, adjust the end mirror of FIB cancellation interferometer (the orange circle in the figure).
3. Finally, adjust the input gain of FIB servo and check that the loop closes.