First we replaced the broken BS oplev PSD and measured BS oplev spectra as shown in the attached figure. The noise floor of BS oplev spectra is fine, but BS suspension moves a lot. In addition, BS pitch can go down with picomotor, but cannot go up. We need to open BS chamber again...

We somehow aligned FC and could see the green flash, but green beam spot at FC transmission moves too much due to BS suspension motion.

Then we found that we cannot maximize TEM00 very well and yaw misalignment cannot be removed. 

We aligned green injection in yaw before as reported in elog2940. We doubt that this could cause some problems. So we tweaked the green injection, but the green flash still had yaw misalignment. After we brought the green injection back to the original alignment, END yaw was misaglined a lot and we had to move the END yaw with picomotor. We went to END room and moved END picomotor with a joystick. However, at some point, END yaw picomotor stopped moving and we lost green flash...

To do list for END mirror:

• center END oplev and check END oplev spectra/transfer function
• install a new picomotor driver to avoid going to END room for picomotor control
• If END oplev spectra are strange or picomotor does not move with the new picomotor driver, open END chamber and check the suspension and picomotor