Vicky, Naoki

We aligned pump AOM and fiber. This time, we aligned AOM from front panel without opening the back panel. So this work can be done with local laser harzard.

We set ISS drivepoint at 0V and measured the AOM throughput. The throughput was 40 mW/62 mW = 65%. We aligned AOM to maximize the throughput and got 59.5 mW/62 mW = 96% throughput.

Then we set ISS drivepoint at 5V and aligned AOM to maximize the 1st order beam. The 1st order beam increased from 3.7mW to 9.1mW. However, when we set the ISS drivepoint at 0V, the AOM output was only 40.5mW. This is already reported in 78519. We aligned AOM to maximize the throughput and got 58.7mW of AOM output.

We repeated this alignment several times as follows.

1st order@5V ISS: 15.8 mW, 0th order@0V ISS: 48 mW, 60mW after alignment

1st order@5V ISS: 16.3 mW, 0th order@0V ISS: 52.4 mW, 56mW after alignment

1st order@5V ISS: 15.3 mW, 0th order@0V ISS: 53 mW

We were getting better AOM throughput at 0V ISS while maitaining the reasonable 1st order beam at 5V ISS. We could improve the alignment more, but we stopped here due to time limitation. 

Finally we aligned the pump fiber.