Andrei, Terry, Naoki

We aligned pump AOM and fiber following 72081.

We set the ISS drivepoint at 0V and measured the AOM throughput. The throughput was 30 mW/60 mW = 50%. We aligned the AOM and got 57 mW/60 mW = 95% throughput.

Then we set the ISS drivepoint at 5V and aligned the AOM to maximize the 1st order beam. The 1st order beam improved from 3.5 mW to 11.5 mW. Then we set the ISS drivepoint at 0V and checked the AOM throughput again. The throughput was only 35mW/60 mW = 58%. We found that bottom screws of AOM for vertical alignment maximized the 1st order beam, but the 0th order beam significantly reduced, which means there is a clipping. This was the case in the last AOM alignment in 77508.

To avoid the clipping, everytime we aligned the AOM and improved the 1st order beam, we made sure that the 0th order beam is not clipped. We ended up with 10.5 mW of 1st order beam and 55 mW of 0th order beam.

After AOM alignment, we aligned the pump fiber, but the fiber alignment did not improve much.

We reverted the OPO trans setpoint from 70 to 80, which was done in 78467.